Stanford Research Systems DS335 Service manual

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MODEL DS335

Synthesized Function Generator

1290-D Reamwood Avenue

Sunnyvale, California 94089

Phone: (408) 744-9040 • Fax: ( 408) 744- 9049

email: info@t hink S RS.c om • www.thinkSRS.com

Revision 1.6 (1/2002)

DS335 Synthesized Function Generator

Table of Contents

Table of Contents i

Condensed Information

Safety and Use iii SRS Symbols iv Specifications v Abridged Command List ix

Getting Started

Introduction 1-1 CW Function Generation 1-1 Frequency Sweep 1-2

Operation

Introd uc tion to DDS 2-1 DS335 Features 2-5

Front Panel Featur es 2-5 Rear Panel Features 2-7

Function Setting 2-9

Setting the Function 2-9

Frequency 2-9 Amplitude 2-9 DC Offset 2-11

Sweeps/FSK 2-13

Frequency Sweeps 2-13

Sweep Type 2-13 Sweep Frequencies 2-14 Sweep/FSK Output 2-14

FSK Intput 2-14

Instrument Setup 2-17

Default Sett ings 2-17

Store and Recall 2-17 GPIB and RS232 Setup 2- 17 Self-Test 2-18

Setup Control Commands 3-6 Status Report ing Commands 3-6 Test and Calibration Commands 3-7 Status Byte Definitions 3-8

Programming Examp les 3-11

Introduction 3-11 GPIB and C Example 3-12 RS232 and BASIC example 3-13

Test and Calibration

Troubleshooting 4-1

Operation Err or Messages 4-1 Self-Test Error Messages 4-2

Performance Tests 4-5

Necessary Equip ment 4-5

Functional Tests 4-6

Front Panel Test 4-6 Self Tests 4-6 Sine Wave 4-6 Square Wave 4-6 Amplitude Flatnes s 4-7 Output Level 4-7

Performance Tests 4-8

Frequency Acc ur ac y 4-8 Amplitude Accurac y 4-8 DC Offset Accuracy 4-9 Subharmonics 4-9 Spurious Signals 4-10 Harmonic Distort ion 4-10 Phase Noise 4-11 Square Wave Rise Time 4-11 Square Wave Symmet ry 4-11

Programming

Programming the DS335 3-1

Communications 3-1

GPIB Communication 3-1 RS-232 Communication 3-1 Data Window 3-1

Command Syntax 3-1 Detailed Command List 3-2

Function Output Commands 3-3 Sweep Control 3-4

Test Scorecard 4-13

Calibration 4-15

Introduction 4-15 Calibration Enable 4-15 Calbytes 4-15

Necessary Equip ment 4-19 Adjustments 4-19

Output Amplifier Bandwidth 4-19 Bessel Filter A djus tment 4-20

DS335 Synthesized Function Generator

ii Table of Contents

Calibration 4-20

Clock Calibration 4-20

DS335 Circuitry

Circuit Descript io n 5-1

Front Panel Board 5-1 Main Board 5-1

Microprocessor S y stem 5-1 Display and Keyboard 5-2 System DAC and S/H's 5-3 DDS ASIC and Memory 5-3 DDS Waveform DAC 5-4 DDS Output Filter s 5-5 Pre-Attenuator 5-5 SYNC Generator 5-5 Function Select ion 5-6 Output Amplifier 5-6 Output Attenuator 5-6

Option Board 5-7

Power Supplies 5-7 GPIB and RS232 Interfac es 5-7

Component Parts Li st 5-9 Schematic Circui t Diagrams Sheet No.

Front Panel

Keypad and LED Display 1/1

Main/Bottom PC Board

Microprocessor 1/8 Display, Keyboard and Cable 2/8 System DACs 3/8 DDS ASIC, Memory, and Sweep 4/8 DDS Waveform DAC and Filters 5/8 SYNC and Pre-Attenuat ors 6/ 8 Output Amplifier 7/8 Regulators and Att enuators 8/8

Option/Top PC Board

Power Supply and Cable 1/2 GPIB and RS232 Interfac es 2/2

Front Panel Compon ent Placement Main PC Board Component Placemen t Option Board Compon ent Placement

DS335 Synthesized Function Generator

Safety and Preparation for Use

WARNING: Dangerous voltages, capable of causing death, are present in this

instrument. Use extreme caution whenever the instru ment covers are remo ved.

This instrument may be damaged if operated with the LINE VOLTAGE SELECTOR set for the wrong ac line voltage or if the wrong fuse is installed.

Safety and Preparation for Use iii

LINE VOLTAGE SELECTION

The DS335 operates from a 100V, 120V, 220V, or 240V nominal ac power source having a line frequency of 50 or 60 Hz. Before connecting the power cord to a power sour ce, verify t hat t he LINE VOLTAGE SELECTOR card, located in the rear panel fuse holder, is set so that the correct ac input voltage value is vis ible.

Conversion to other ac input voltages requires a change in the fuse holder voltage card position and fuse value. Disconnect the power cord, open the fuse holder cover door and rotate the fuse- pull lever to remove the fuse. Remove the small printed circuit board and select the operating voltage by orienting t he board so that the des ired voltage is visible when it is pushed f irmly bac k into its slot. Rotate the fuse-pull lever back into its normal position and insert the corr ect fuse into the fuse holder.

LINE FUSE

Verify that the correct line fuse is installed before connecting the line cord. For 100V/120V, use a 1 Amp slow blow fuse and for 220V/240V, use a 1/2 Amp slow blow fuse.

LINE CORD

The DS335 has a detachable, three-wire power cord for connection to the power source and to a protective ground. The exposed metal parts of the instrument are connected to the outlet ground to protect against electrical shock. Always use an outlet which has a properly connected protective ground.

DS335 Synthesized Function Generator

iv SRS Symbols

DS335 Synthesized Function Generator

SPECIFICATIONS

FREQUENCY RANGE

Specifications v

OUTPUT

AMPLITUDE

Waveform Maximum Sine 3.1 MHz 1 µHz ±25ppm Square 3.1 MHz 1 µHz ± 25ppm Ramp 10 KHz 1 µHz ±25ppm Triangle 10 KHz 1 µHz ±25ppm Noise 3.5 MHz (Gaussian Weighting)

Source Im pedance : 50 Ω Output may float up to ±40V (AC + DC) relat iv e to earth ground.

Range into 50Ω load (limited such that | V

Function Max. Min. Max. Min.

Sine 10V 50 mV 3.54V 0.02Vrms Square 10V 50 mV 5.00V 0.03Vrms Triangle 10V 50 mV 2.89V 0.01Vrms Ramp 10V 50 mV 2.89V 0.01Vrms Noise 10V 50 mV 1.62V 0.01Vrms

Freq Resolution Accuracy

| + |Vdc | ≤ 5 V)

ac peak

Vpp Vrms

Range into a high impedance load (limited s uc h that |V

Vpp Vrms

Function Max. Min. Max. Min.

Sine 20V 100 mV 7.07V 0.04Vrms Square 20V 100 mV 10V 0.05Vr m s Triangle 20V 100 mV 5. 77V 0.03V r m s Ramp 20V 100 mV 5. 77V 0.03V r m s Noise 20V 100 mV 3.24V 0.02Vrms

Resolution 3 digits Accuracy (with 0V DC Offset) , 50ΩΩΩΩ terminated

Sine: Accuracy

± 0.1 dB

Square: Accuracy

± 2%

Triangle, Ramp: Accur ac y

±2%

| + |Vdc| ≤ 10 V)

ac peak

DS335 Synthesized Function Generator

vi Specifications

DC OFFSET

Range: ±5V into 50 Ω (limited such that | V

Limitation: |V Resolution: 3 digits

Accuracy: 1.2% of s etting (DC only)

WAVEFORMS

Sinewave Spectral P urity

Spurious (non-harmonic ) : ≤ -65 dBc to 1 MHz Phase Noise: ≤ - 60dB c in a 30 KHz band centered on the carrier, Subharmonic: ≤ -70 dBc

Harmonic Distort ion: Harmonically related s ignals will be les s than:

| + |Vdc | ≤ 5 V)

ac peak

±10V into hi-Z (limited such that | V

| ≤ 2xVpp in all cases

| + |Vdc | ≤10 V)

ac peak

±0.8 mV to ±80 mV depending on AC and DC settings

≤ -55 dBc to 3.1 MHz

exclusive of disc r ete spurious signals

Level Frequency Range

≤ -60 dBc ≤ -50 dBc ≤ -40 dBc

DC to 100 KHz .1 to 1 MHz 1 to 3.1 MHz

Square Wa v e

Rise/Fall Time: < 15 nS ±5 nS (10 to 90%), at full output Asymmetry: < 1% of period + 3 nS Overshoot: < 5% of peak to peak amplitude at full out put

Ramps and Triangle

Rise/Fall Time 100 ±20 nS (3.5MHz Bessel Filter ) Linearity ±0.1% of full scale output Settling Time < 200 ns to settle within 0. 5% of f inal v alue at f ull output

FREQUENCY SWEEP

Type: Linear or Log, phase continuous Waveform: Up, down, up-down, single sweep Rate: 0.01 Hz to 1 kHz Span: 1 µHz to 3.1 MHz (10 kHz for triangle or ramp)

FREQUENCY-SHIFT KEYING (FSK)

Type: Internal r ate or External control, phase continuous Waveform: Sine, Square, Triangle, Ramp Rate: 0.01 Hz to 50 kHz (internal) Shift Span: 1 µHz to 3.1 MHz (10 kHz for triangle or ramp) External: TTL input, 1MHz maximum

DS335 Synthesized Function Generator

SYNC & SWP/FSK OUTPUTS

SYNC: TTL level, active with all functions SWP/FSK: TTL level, synchronous with internal Sweeps and FSK rates

TIMEBASE

Accuracy ±25 ppm (0 to 70° C) Aging 5 ppm/year

Optional Timebas e

Type: T em per ature Compensated Crystal Oscillator Stability: +/- 2.0 ppm, 0 to 50°C Aging: 5 ppm first year, 2 ppm per year t her eaft er

GENERAL

Interfaces RS232-C (300 to 9600 Baud, DCE) and GPIB. Weight 8 lbs.

Dimensions 8.5" x 3.5" x 13" (W x H x L) Power 25 Watts, 100/120/220/ 240 V ac 50/60 Hz

Specifications vii

All instrument functions can be controlled over t he interfaces.

DS335 Synthesized Function Generator

viii Specifications

DS335 Synthesized Function Generator

Abridged Command List ix

Abridged Command List

Syntax

Variables i,j are integer s. Variable x is a real number in int eger , real, or exponential notation. Commands which may be queried have a ? in parentheses (?) after the mnemonic. The ( ) are not sent. Commands that may only be queried have a '?' after the mnemonic. Commands which may not be queried have no '?'. Optional param eters are enclosed by {}.

Function Output Control Commands AECL Set s the output amplitude/offs et t o E C L levels (1V pp, -1.3V offset).

AMPL(?) x Sets the output amplitude to x. x is a value plus units indicator. The units c an

be VP (Vpp), VR (Vrms). Example: AM P L 1.00VR s ets 1.00 Vrms.

ATTL Sets the output am plitude/offset to TTL levels (5 Vpp, 2. 5 V offset). FREQ(?) x S ets the output frequency t o x Hz. FUNC(?) i Sets the output function. 0 = sine, 1 = square, 2 = triangle, 3 = ram p,

4 = noise.

INVT(?)i Sets the output inversion on (i=1) or off (i=0). Used with the ramp function. KEYS(?) i Simulates a key pr ess or r eads the m ost r ec ently pressed key. OFFS(?)x Sets the output offset to x volts. SYNC(?) i Turns the Sync output on (i=1) or off (i=0). TERM(?) i Sets the output source impedance to 50Ω (i=0), Hi-Z (i=1).

Sweep control command s FSEN(?) i Enables FSK on (i=1) or off (i=0). Valid only if SDIR2 is sent first.

*TRG Triggers single sweeps if in single trigger mode. SDIR(?)i Sets the sweep direction 0 = Ramp, 1 = Triangle, 2 = FSK. SPFR(?) x Sets the sweep stop frequency to x Hz. SRAT(?) x Sets the sweep rate to x Hz. STFR(?) x Sets the sweep start frequency t o x Hz. STYP(?) i Sets the sweep type. 0 = linear sweep, 1 = logarithmic sweep. SWEN(?) i Turns sweeps on (i=1) or off (i=0). TSRC(?) i Sets the trigger s our c e for s weeps . 0 = single, 1 = internal sweep rate.

Setup Control Command s *IDN? Ret urns the device identif ic ation.

*RCL i Recalls stored setting i. *RST Clears instrument to default settings. *SAV i Stores the current settings in storage location i.

Status Reporting Co mmand s *CLS Clears all status r egisters.

*ESE(?) j Set s /reads the standard status byte enable register. *ESR? {j} Reads the standard status regist er, or just bit j of register. *PSC(?) j Sets the power on status clear bit . T his allows SRQ's on power up if desired. *SRE(?) j Sets/reads the serial poll enable regis ter. *STB? {j} Reads the serial poll regis ter, or just bit n of register. STAT? {j} Reads the DDS status register, or just bit n of register. DENA(?) j Sets/reads the DDS status enable regist er.

DS335 Synthesized Function Generator

x Abridged Command List

Hardware Test Control *TST? Starts self-test and returns status when done.

Status Byte Definitions

Serial Poll Status Byte bit name

0 Sweep Done set when no sweeps in progress 1 Sweep Enable set when sweep or FSK is enabled 2 User SRQ set when the user issues a front panel SRQ 3 DDS set when an unmasked bit in DDS status byte is set 4 MAV set when GPIB output queue is non- empty 5 ESB set when an unmasked bit in std event status byte is set 6 RQS SRQ bit 7 No Command set when there ar e no unex ecuted commands in input queue

Standard Event Status Byte bit name

0 unused 1 unused 2 Query Error s et on output queue overflow 3 unused 4 Execution Err set on err or in command execution 5 Command Err set on command syntax error 6 URQ set on any front panel key press 7 PON set on power on

DDS Status Byte

usage

bit name 0 Trig'd set on sweep trigger 1 Not in use 2 Not in use 3 Not in use 4 Warmup set when the DS335 is warmed up 5 Test Error set when self test fails 6 Not in use 7 mem err set on power up memory error

usage

DS335 Synthesized Function Generator

Getting Started 1-1

Getting Started

Introduction This section is designed to f amiliarize you with the operation of the DS335

Synthesized Function Generator. The DS335 is a powerful, flexible generator capable of producing both continuous and swept waveforms of exceptional purity and resolution. The DS335 is also relatively sim ple to use, and the following examples will lead you step-by-st ep through some typical uses.

Data Entry Setting t he DS335's operational par amet ers is done by pres sing the key wit h

the desired parameter's name on it (FREQ, for example, to set the frequency). The c ur r ent value will be dis play ed. Some of the parameters are labeled above the keys in light gr ay. To display those values first press the SHIFT key and then the labeled key ([SHIFT][ STOP FREQ], for example, to display the type of wavef orm sweep set). Values ar e changed by the DATA ENTRY keys. To directly enter a value simply type t he new value using the keypad and complete the entry by hitting one of t he UNITS key s. If the v alue has no particular unit s any of the UNIT S keys may be used, other wise select the appropriate units key. If an error is made, pressing the corresponding function key will backspace the cursor. If the key is pressed repeat edly the display will eventually show the previous value. For example, if a new frequency is being entered and the wrong numeric key is pressed, then pressing the FREQ key will backspace the cursor. If the FREQ key is pressed until the new entry is erased, then t he last valid frequency v alue will be displayed. The current parameter value may also be incremented or decremented using the UP and DOWN ARROW keys. Pressing the UP ARROW key will increment the flashing digit value by one, while press ing the DOWN ARROW key will decrement the flashing digit value by one. If the parameter value cannot be incremented or decremented, the DS335 will beep and display an error message. Pressing [SHIFT][UP ARROW] or [SHIFT][DOWN ARROW] changes the position of the blinking digit.

CW Function Gene r a t io n Our first example demonstrates a CW waveform using the DS335's data

entry functions. Connect the front panel FUNCTION output to an oscilloscope, ter minating the output into 50 ohms. Turn the DS335 on and wait until the message "TEST PASS" is displayed (if the self tests fail, refer to TROUBLESHOOTING section of the manual).

1) Press [SHIFT][+/-]. This rec alls the DS335's default settings.

2) Press [AMPL]. Then press [5][Vpp]. Displays the amplitude and sets it to 5 Vpp. The scope should show a 5 Vpp 1 MHz sine wave.

3) Press [FUNC DOWN ARROW] twice. The function should change to a square wave and then a triangle wave. The DS335 automatically performs a frequency adjustment to match the maximum triangle frequency (10kHz ) .

4) Press [FREQ] and then [1][kHz]. Displays the frequency and sets it to 1 kHz. The scope should now display a 1 kHz triangle wave.

5) Press [UP ARROW]. The frequency will increment to 1.0001 kHz. The flashing digit indicates a st ep s iz e of 0. 1 Hz.

DS335 Synthesized Function Generator

1-2 Getting Started

6) Press [SHIFT UP ARROW] twice. Observe that the blinking digit is shifted twice to the left indicating a step size of 10 Hz.

7) Press [UP ARROW] thr ee times . We've changed t he output frequency to 10.0301 kHz.

Frequency Sweep The next example demonstrat es a linear frequency sweep. The DS335 c an

sweep the output frequency of any function over the entire range of allowable output frequencies. There are no restrictions on minimum or maximum sweep span. The sweep is phase continuous and may range from 0.01Hz to 1000 kHz.

Attach the FUNCTION out put BNC to t he os cilloscope, terminating the output into 50 ohms. S et the scope to 2V/div. Attach the SWEEP rear-panel BNC to the scope and set to 2V/div. The s cope should be set to trigger on t he rising edge of this s ignal.

1) Press [SHIFT][+ /-]. This recalls the DS335's default s ett ings.

2) Press [AMPL] then [5][ V pp]. Sets the amplitude to 5Vpp.

3) Press [SHIFT] [STO P FREQ]. Verify linear sweep. "Lin" should be blinking now.

4) Press [SWE EP RATE] then [1][0][0] [Hz ]. Set the sweep rate t o 100 Hz . The s weep will take 10 ms (1/100Hz). Set t he scope time base to 1ms/div.

5) Press [START FREQ] then [1][0][0][kHz]. Set the sweep start frequency to 100 kHz.

6) Press [STOP FREQ] then [1] [MHz ]. Set the stop frequency to 1 MHz.

7) Press [SHIFT][START FREQ]. The SWP LED will light, indicating that the DS335 is sweeping. The scope should show the SWEEP output as a TTL pulse synchronous with the start of the sweep. The FUNCTION output is the swept sine wave. The DS335 also displays the option to switching to single shot sweeps at this time. Pressing the up or down arrows at this time switches the sweeps to single shot. Pressing [SHI FT][START F REQ] triggers one sweep.

DS335 Synthesized Function Generator

Introduction 2-1

Introduction to Direct Digital Synthesis

Introduction Direct Digital Synthesis (DDS) is a method of generating very pure

waveforms with extraordinary f requency resolution, low frequency switching time, crystal clock-like phase noise, and flex ible s weeping c apabilities. A s an introduction to DDS let's review how traditional funct ion generators work.

Traditional Generator s Frequency synthesized function generators ty pically use a phase-lock ed loop

(PLL) to lock an oscillator to a stable reference. Wave-shaping circuits are used to produce the desired function. It is difficult to make a very high resolution PLL so the frequenc y resolution is usually limited to about 1:10 (some sophistic ated fractional-N PLLs do have much higher r es olution). Due to the action of the PLL loop filter, these synthesizers typically have poor phase jitter and fr equency switching respons e. In addition, a separate waveshaping circuit is needed f or each t ype of waveform desired, and these of ten produce large amounts of waveform distort ion.

DDS DDS works by generating address es to a waveform ROM to produce dat a for

a DAC. However, unlike earlier techniques, the clock is a fixed frequency reference. Instead of using a counter to generate addresses, an adder is used. On each clock cycle, the contents of a Phase Increment Register are added to the contents of the Phase Accumulator. The Phase Accumulator output is the address to the waveform ROM (see diagram below). By changing the Phase Increment the number of clock cycles needed to step through the entire waveform ROM changes, thus changing the output frequency.

Figure 1: Block diagram of S RS DDS ASIC

Frequency changes now can be accomplished phase continuously in only one clock cycle. And the fixed clock eliminates phase jitter, requiring only a simple fixed fr equenc y anti-aliasing filter at t he output.

The DS335 uses a custom Application Specif ic Integrated Circuit (ASIC) to implement the address generation in a single component. The frequency resolution is equal to the resolution with which the Phase Incr ement can be set. In the DS335, the phase registers are 48 bits long, resulting in an impressive 1:10 control CPU that operat es on the Phase Accumulat or, P hase Inc rement, and external circuit ry to allow digital synthesis and contr ol of waveform sweeps. The Modulation CPU uses data stored in the Modulation RAM to produce frequency sweeps. All modulation par ameters, such as rate, and frequency deviation, are digitally programmed.

frequency resolution. The ASIC also contains a modulation

DS335 Synthesized Function Generator

2-2 Introduction

DS335 Description

DDS gives the DS335 greater flexibility and power than conventional synthesizers without the drawbacks inherent in PLL designs.

Figure 2: DS335 Bloc k Diagram

A block diagram of the DS335 is shown in Figure 2. T he heart of the DS335 is a 10 MHz crystal clock. The 10 MHz clock controls the DDS ASIC, waveform ROM, and high-speed 12bit DAC. Sampling theory limits the frequency of the waveform output from the DAC to about 40% of 10 MHz, or 3 MHz. The 48 bit length of the ASIC's PI R' s s ets the frequency resolution to about 36 nHz. These parameters and the DA C's 12 bit resolution define the performance limits of the DS335.

The reconstruction filter is key to accurately reproducing a waveform in a sampled data system. The DS335 contains two separate filters. For sine wave generation the output of the DAC goes through a 7 while ramps, and triangles pass instead through a 3.5 MHz 5

order Cauer filter,

order Bess el filter. The Cauer filter has a c utoff frequency of 3.4 MHz and a stopband attenuation of 86 dB, and includes a peaking circuit to correct for the sin(x)/x amplitude response characteristic of a sampled system. This filter eliminates any alias frequencies from the waveform output and allows generation of extr emely pure sine waves. However, the Cauer filter has very poor time response and is only useful for CW waveforms. Therefore, the Bessel filter was chosen for its ideal time response, eliminating rings and overshoots from stepped waveform outputs.

The output from the filter passes thr ough pre-amplif ier attenuat ors wit h a 0 to 14 dB range. The attenuators are followed with a wide bandwidth power amplifier that outputs a 10 V peak-to-peak into a 50 ohm load with a ris e time of less than 15 ns. The output of the power am plifier passes through a series of four step attenuators (2, 4, 8, and 16 dB) that set the DS335's final out put

DS335 Synthesized Function Generator

Introduction 2-3

amplitude. The post amplifier attenuators allow internal signal levels to remain as large as possible, minimizing output nois e and s ignal degr adation.

Square waves and waveform sync signals are generated by discriminating the function waveform with a high-speed comparator. The output of the comparator pass es to the SYNC OUTPUT and, in the c ase of square waves, to the amplifier input . G enerating square waves by discriminating the sine wave signal produces a square wave output with rise and fall times much faster than allowed by either of the signal filters.

DS335 Synthesized Function Generator

2-4 Introduction

DS335 Synthesized Function Generator

Front Panel Features

Features 2-5

1) Power Switch The power switch turns the DS335 on and off. The DS335 has a battery

backed up system RAM that remembers all inst rument settings.

2) Data Entry Keys The numeric keypad allows for direct entry of the DS335's parameters. To change a parameter value s im ply type the new value. Ent r ies are terminat ed by the UNITS keys. A typing error may be corrected by pressing the corresponding function key. For example, if the wrong numeric key is pressed while entering a new frequency, pressing the [FREQ] key will backspace over the last entered digit. If there are no digits left, the current frequency value is displayed. The [+/-] key may be selected at any time during numeric entry .

3) Units Keys The UNIT keys are used t o terminate numer ic entries. Simply press the key with the desired units to enter the typed value. Some parameters have no particular units and any of the unit keys may be used.

The unit keys also increase and decrease the num eric value in the DS335's display. Pressing t he [UPARROW] key adds one to the flashing digit value, the [DOWN ARROW] key subtracts one from the flashing digit value. To change the position of the flashing digit, press [SHIFT] [LEFT ARROW] or [SHIFT] [RIGHT AR ROW]. A few of the display menus have more t han one parameter displayed at a time. The [SHIFT][LEFT ARROW] and [SHIFT][RIGHT ARROW ] key s select between left and right.

4) Shift Key The shift key s elects the function printed abov e the keys. Pressing [SHIFT] and then the desired key to select the specific function (for example [SHIFT][50Ω] sets the source impedance to 50Ω. When the SHIFT key is pressed the SHIFT LED will light. Pressing [SHIFT] a second time will deactivate shif t m ode.

DS335 Synthesized Function Generator

2-6 Features

5) Sweep Key These keys control t he different s weep parameters inc luding: St art and Stop

Frequencies, Sweep Rate, Continuous or Single Sweep, Linear or Log Sweep, Unidirectional or Bidirectional Sweeps, and FSK.

6) Function Keys These keys control the main function output. The Func [DOWN ARROW] key and [SHIFT][UP ARROW] key select between the output functions. If the output frequency is set beyond the range allowed for a waveform (> 10kHz for triangle and ram p) an error message will be displayed and the f requency will change to the maximum allowed for that function.

7) Main Function BNC This output has an impedance of 50Ω. The shield of this output may be floated up to ±40V relative to earth ground.

8) Sync Output BNC This output is a TTL squar e wave synchronized to the main function out put and has a 50Ω output impedance. The shield of this out put may be float ed

up to ±40V relative t o earth gr ound.

9) Status LEDs These four LEDs indicate the DS335's st atus. They are: name function

REMOTE The DS335 is in GPIB remote state. The [3] key r eturns local

control. GPIB Flashes on GPIB activity. RS232 F las hes on RS 232 activity. ERROR Flashes on an error in the execution of a remote or local

command including range error s .

10) Parameter Displ ay The 8 digit display shows the v alue of the c ur r ently displayed parameter. The LEDs below in the DISPLAY section indicate which parameter is being displayed. Error messages also appear on the display. When an error message is displayed you c an return to the normal display by pressing any key.

11) Units LEDs The Units LEDs indicate the units of the displayed param eter . If no LED is lit the value has no units. The SWP LED indicates that a sweep or FSK is in progress.

12) Load Impedance LEDs These LEDs indicate the load impedance value as set by the user. The amplitude and offset display values will change according to the load impedance setting.

DS335 Synthesized Function Generator

Rear Panel Features

Features 2-7

1) Power Entry Module This contains the DS335's fuse and line voltage select or. Use a 1 amp slow

blow fuse for 100/120 volt operation, and a 1/2 amp fuse for 220/240 volt operation. To set the line volt age selector for the correct line voltage, firs t remove the fuse. Then, remove the line voltage select or card and rotate t he card so that the correct line voltage is dis played when the card is reinsert ed. Replace the fuse.

2) Sweep/FSK Outpu t This output generates a TTL pulse that is synchronous with the DS335's frequency sweep. When the DS335 is in FSK mode, the output voltage reflects the present frequency at the FUNCTION output BNC (TTL LOW = Start Frequency , TTL HIGH = Stop Frequency). The shield of this output is tied to that of the function output and may be floated up to ±40V relat ive to earth ground.

3) FSK Input The Fr equency-S hift Key ing input allows t he user to toggle between the st art frequency and the stop frequency. The BNC takes a TTL level input. When the input is low the st art frequency is active, and when the input is high the stop frequency is act i v e. This input is s am pled at 10 MHz.

4) GPIB Connector If the DS335 has t he optional GPIB/RS232 interface this c onnector is used for IEEE-488.1 and .2 compatible communications. The shield of this

connector i s connect ed to earth ground.

5) RS232 Connector If the DS335 has t he optional GPIB/RS232 interface this c onnector is used

for RS232 communication. The DS335 is a DCE and accepts 8 bits, no parity, 2 stop bits at between 300 and 9600 Baud. The shield of this

connector i s connect ed to earth ground.

DS335 Synthesized Function Generator

2-8 Features

DS335 Synthesized Function Generator

Function Setting 2-9

DS335 OPERATION

Introduction The following sections describe the operation of the DS335. The first section

describes the basics of setting t he function, frequenc y, amplitude, and off set. The second section explains sweeps and FSK. The third section explains storing and recalling setups, running s elf-t est and autoc alibration, and set ting the computer interfaces.

Power-On When the power is first applied t o the DS335 the unit will display its s erial

number and ROM version for about three seconds. Then, the DS335 will initiate a series of self-tests of the c ircuitry and stored data. The test should take about three seconds and end with the message "TST PA SS". If the self test fails the DS335 will display an err or message indicat ing the nat ure of the problem (see the TROUBLESHOOTING section for more details). The DS335 will still attem pt to operate normally after a self-test failure, pressing any key will erase the error message.

SETTING THE FUNCTION

OUTPUTS The FUNCTION and SYNC BNCs are the DS335's main outputs. Both of

these outputs ar e f ully floating, and their shields may be floated relative to earth ground by up to ±40V. Both outputs also have a 50Ω output impedance. If the out puts are terminated into high impedance instead of 50W the signal levels will be twice those programm ed (the FUNCTION output may also show an increase in wavefor m dist ortion). The output im pedance should be set properly from the front panel using the [SHIFT][ 5] or [SHIFT][6] keys. Incorrect impedance matching may result in output voltages that do not correspond to the displayed amplitudes and offsets. For example, if the DS335 is set for a 50 Ohms source impedance and the output is connec ted to a scope without a 50 Ohms ter minator, then t he scope waveform will be twice the amplitude displayed on the DS335.The programmed waveform comes from the FUNCTION output , while the SYNC output generat es a T TL compatible (2.5 V into 50Ω) signal that is synchronous with the function output. The SYNC signal is suppressed if the function is set to NOISE or ARB. The SYNC signal can be disabled and enabled with the [S HIF T] [0] and [SHIFT][.] keys.

FUNCTION SELECTION The DS335's output function is selected using the FUNCTION UP/DOWN

arrow keys. Simply press the keys until the desir ed function LED is lit. If the programmed frequency is outside of the range allowed for the selected

DS335 Synthesized Function Generator

2-10 Function Setting

function, an err or message will be displayed and the f requency will be set to the maximum allowed f or that function.

Ramps Ramp functions usually ramp up in voltage, downward ramps may be set

entering a negative amplit ude ( see AMPLITUDE section).

FREQUENCY To display the DS335's output frequency press t he [FREQ]. The frequency

units can be Hz, kHz, or MHz, and ar e indicated by the LE Ds on the r ight of the display. The DS335 has 1 µHz frequency resolution at all fr equencies, for all functions . The maximum frequenc y depends on the f unction selected as shown below.

Function Frequency Range

Sine Square Triangle Ramp

1 µHz → 3.100000000000 MHz 1 µHz → 3.100000000000 MHz 1 µHz → 10,000.000000 Hz 1 µHz → 10,000.000000 Hz

Noise 3.5 MHz White Noise (fixed)

Frequency is usually displayed by the DS335 with the highest resolution possible. However, if t he frequency is below 100 Hz, the DS335 will display the frequency wit h 1 µHz resolution. At frequencies greater than 1 MHz the digits below 0.1 Hz cannot be displayed, but the frequency still has 1 µHz resolution and may be set via the computer interfac es.

If the function is set to NOISE the charact er of the noise is fixed wit h a band limit of 3.5 MHz. The frequency is not adjus table and the FREQ display will read "noise" instead of a numerical value.

Setting the Frequency To set the frequency of any f unction simply t ype a new value on the k eypad

and complete the entr y with the appropriate units (Hz, kHz, or MHz). Also, the UP and DOWN arrow keys may be used to increm ent or decrement the frequency by adding or s ubtracting one from the flashing digit.

AMPLITUDE Press [AMPL] to display t he amplitude of the output func tion. T he amplitude

may be set and displayed in units of V

and V

. The current units are

rms

indicated by the LEDs at the right of the display. The amplitude range is limited by the DC offset setting since |V

| + |Vdc| ≤ 5 V (into 50Ω). If

ac peak

the DC offset is zero the amplitude range for each of the functions is shown below:

Note: The rms value for NOISE is based on the total power in the output bandwidth (about 3.5 MHz) at a given peak to peak setting.

Function Max. Min. Max. Min.

Sine 10V 50 mV 3. 54V 0.02Vrms Square 10V 50 mV 5.00V 0.03Vrms Triangle 10V 50 mV 2.89V 0.01Vrms Ramp 10V 50 mV 2. 89V 0.01Vrms Noise 10V 50 mV 1.62V 0.01Vrms

50ΩΩΩΩ Load Impedance

DS335 Synthesized Function Generator

Vpp Vrms

Function Setting 2-11

Vpp Vrms

Function Max. Min. Max. Min.

Sine 20V 0.1V 7.07V 0.04Vrms Square 20V 0.1V 10.0V 0.05Vrms Triangle 20V 0.1V 5.77V 0.03Vrms Ramp 20V 0.1V 5.77V 0.03Vrms Noise 20V 0.1V 3.24V 0.02Vrms

HIGH-Z Load Impedance

Output Inversion The DS335's output may be invert ed f or r amp functions. This is useful for

turning positive ram ps into negative ramps. E ntering a negative am plitude inverts the ramp out put.

D.C. Only The output of the DS335 may be s et to a DC level by entering an amplitude

of 0 V. When the amplitude is set to zero the A.C. waveform will be completely shut off and the DS335 may be used as a DC voltage source.

DC OFFSET When the [OFFS] key is pressed the DC offset is displayed and the V

indicator LED will be lit. A new value may be entered numerically with any amplitude unit key. In general, the DC offset may range bet ween ±5V, but is restricted such that |V

| ≤ 10 V (into HIGH-Z). The DC offset is also restric ted such that |Vdc| ≤

2 x V

. When the offset is changed, the out put signal will briefly go to zero

| + |Vdc| ≤ 5 V (into 50 Ohms), or | V

ac peak

| +

as the output attenuators are switched, and then back to t he set offset value.

SYNC ENABLE Pressing the [SHIFT] [.] key enables the SYNC OUT function. The

[SHIFT][0] disables the output by highly attenuating the output function signal.

DS335 Synthesized Function Generator

2-12 Function Setting

DS335 Synthesized Function Generator

Sweeps & FSK 2-13

FREQUENCY SWEEPS & FSK

Introduction The DS335 can perform frequency sweeps of the sine, s quare, tr iangle, and

ramp waveforms. The sweeps may be up or down in frequency, and may be linear or logarithmic in nat ure. The frequency c hanges during the sweep ar e phase continuous and the sweep rate may be set between 0.01 Hz and 1000Hz. The DS335 has a SWEEP output that may be used to trigger an oscilloscope. The DS 335 is also capable of Frequency-Shift Keying (FSK). FSK can be implemented either through the internal rate generator or the back panel external input to toggle between two pres et frequencies.

Sweep/FSK Enable Sweeps are enabled by pressing [SHIFT][START FREQ] in the Frequency

Sweeps menu. The DS335 displays the "CONT SNGL" menu which allows the user to choose between cont inuous and single s weeps. T he DS335 will immediately start a cont inuos sweep unless the user pres ses the UP/DOWN arrow key to select SING LE s weep. Once a single sweep is s elected, the [SHIFT][START F REQ] key triggers the sweep. If t he user has select ed the FSK function fr om t he " UNI/BI" (Unidirectional/Bidirec tional/FSK) menu, t he single/continuous sweep option is disabled and t he "FS OFF" menu appears, giving the user the choice to enable or disable the F SK function. Once the FSK function is selec ted and enabled, the FSK output signal appears at the Function Out BNC.

Sweep Type Pressing the [SHIFT ] [STOP FREQ] key sets the sweep to either a linear or

log mode. The UP/DOWN arrow toggles between t he two sweep types. The output frequency of a linear sweep changes linearly during the sweep tim e. The output frequency in a logarithmic sweep changes exponentially during the sweep time, spending equal time in each decade of frequency. For example, in a sweep fr om 1 kHz to 100 kHz, the sweep will spend half the time in the 1 kHz to 10 kHz range and half the time in t he 10 kHz t o 100 kHz range). It should be noted that these are digital sweeps, and that the sweep is actually composed of 1500 to 3000 discrete f requency points, depending on the sweep rate.

Sweep Waveform The type of sweep waveform may be set to UNIdirectional (ramp) or

BIdirectional (t riangle) by pres sing the [ SHIFT][SWE EP RATE] key and then pressing the UP/DOWN arrow keys. If FSK is selected, Frequency-Shift keying is enabled and the sweeps are disabled. If the waveform is UNI (Ramp) the DS335 sweeps f rom the start to t he stop frequency, r et urns to the start frequenc y and repeats continuously. For BI directional sweeps the DS335 sweeps from the st art t o the stop frequency, then s weeps from the stop frequency to t he start frequency, and repeat s. If the DS335 is set for a single sweep, the sweep oc c ur s only onc e.

DS335 Synthesized Function Generator

2-14 Sweeps & FSK

Sweep/FSK RATE The duration of the sweep is set by [RATE], and the value is entered or

modified with the keypad. The sweep rate may be set over the range of

0.01 Hz to1 kHz. The sweep rate is the inverse of t he sweep time, a 0. 01 Hz rate is equal to a 100s sweep tim e, and a1 kHz rate is equal to a 1 ms sweep time. For a TRIANGLE sweep the sweep time is the total time t o sweep up and down. If FSK is selected fr om the UNI/BI menu, then the "Sweep Rate" button sets the FSK Rate. If the rate is set to 0 Hz t hen the rear panel F SK BNC input toggles between the two preset frequencies. For any non zero rate the DS335 will toggle between the two preset frequencies at the specified rate. The max imum internal FSK rate is 50 kHz.

Sweep/FSK FREQUENCI ES The DS335 may sweep over any portion of its frequency range: 1 µHz to

3.1 MHz for sine and square wav es, 1 µHz to 100 kHz for triangle and ramp waves. The sweep span is limited to six decades for logarithmic sweeps. The DS335's sweep range is set by entering the start and stop frequenc ies. In FSK mode, the DS335 will toggle bet ween any two frequencies: 1µHz to

3.1 MHz for sine and square waves, and 1 µHz to 100 kHz for triangle and ramp waves. There are no rest rictions on the values of the st art and stop frequencies for linear sweeps.

Start and Stop Frequencies To enter the start and stop f requency press the [START F REQ] and [STOP

FREQ] keys. The span value is restricted to sweep frequencies greater than zero and less than or equal t o the maximum allowed frequency. If the stop frequency is greater than the start frequency, the DS335 will sweep up. If the start frequency is larger the DS335 will sweep down. If FSK is enabled the DS335 toggles between the Start and Stop frequencies at the Sweep/FSK Rate. If the rate has been set to zero then the rear panel FSK input is active. A TTL low level activat es the start frequency and a TTL high level activat es the stop frequency.

Sweep/FSK OUTPUT The rear-panel SWP/FSK output is synchronous with the sweep rate. This

output emits a TTL pulse at t he beginning of every sweep cycle and can be used to trigger an oscilloscope. When the start frequency is selected, the Sweep output is at 0 Volts, and when the Stop frequency is selected the Sweep level is at 5 Volts. The Sweep output is synchronous with the frequency shifts.

FSK Input The FSK input accepts TTL level signals. When enabled (FSK mode with

0 Hz rate), it is sampled at a 10 MHz frequenc y by the DS335. A low TTL level selects the start frequency, and a high TTL level selects the stop frequency (see example below). When the FSK Input is being used, the Sweep output is disabled and stays at 0 Volts.

DS335 Synthesized Function Generator

External Frequency-Shift Keying (FSK) Example

Sweeps & FSK 2-15

DS335 Synthesized Function Generator

2-16 Sweeps & FSK

DS335 Synthesized Function Generator

DS335 Setup 2-17

INSTRUMENT SETUP

Introduction This section describes the DS335's default settings, storing and recalling

settings, s ett i ng the computer interfaces, and running self-test.

Default Settings Press [SHIFT][+/-] to recall the DS 335' s default settings . The DS335's default

settings are listed below:

Setting Default Value

Frequency 1 MHz Function Sine

SYNC ON/OFF On Load Impedance 50Ω

Display Frequency Amplitude 1 Vpp

Offset 0.0 V Inversion Off

Sweeps Off Start Frequency 1Hz Stop Frequency 3.1MHz Trigger Source Continuous Sweep/FSK Rate 100 Hz

Interface RS232 Baud Rate 9600 GPIB Address 22

Storing Setups To st ore t he DS335's current setup press [SHIFT][7] followed by a loc ation

number in the range 0 - 9. After pressing any UNITS key to enter the location number, the message "sto done" will be displayed, indicating that the settings have been s tored.

Recalling Stored Settings T o recall a stored setting press [SHIFT][8] followed by a loc ation number in

the range 0 - 9. After press ing any UNITS key to enter the location number the message "rcl done" will be displayed, indicating that the settings have been recalled. If nothing is s tored in the selec ted location, or the s ett ings are corrupted, t he message "rcl err" will be displayed.

GPIB Setup To set the DS335's GPIB interface press [SHIFT][1]. The GPIB enable

selection will be displayed. Use the [UP ARROW] and [DOWN ARROW] keys to enable the GPIB interface. Press [SHIFT][1] again to display the GPIB address. Enter t he addr es s desired us ing the numeric key pad or arrow keys. The range of valid address es is 0 - 30.

NOTE: If the DS335 does not have the optional GPIB/RS232 int erfaces the message "no GPIB" will be displayed when the GPIB menu is accessed. Only one of the GPIB and RS232 interf aces may be active at a given time, the RS232 interfac e is autom atically disabled when GPI B is enabled.

DS335 Synthesized Function Generator

2-18 Sweeps & FSK

RS232 Setup To set the DS335's RS232 interface press [SHIFT][2]. The RS232 enable

selection will be displayed. Use the UP/DOWN ARROW keys to enable the RS232 interface. Press [SHIFT][2] again to display the RS232 baud rate selection. The available baud rates of 300, 600, 1200, 2400, 4800, or 9600 baud can be set with the UP/DOWN ARROW keys .

NOTE: If no interface option is present the message "no RS232" will be displayed when the RS232 menu is accessed. Only one of the GPIB and RS232 interfaces may be active at a given time, the GPIB interface is automatically disabled when RS 232 is enabled.

User Service Requests While the GPIB is enabled the user m ay is sue a service request (SRQ) by

pressing [SHIFT ][4]. The message "srq sent" will be displayed, and the GPIB LED will light. The GPIB LED will go off after the host computer does a serial poll of the DS335. Note: the user service request is in addition to t he usual service request s based on status conditions ( see PROGRAMMING section for details).

Communication s Dat a Press [SHIFT][2] three tim es t o dis play the last 256 characters of data that

have been received by the DS335. This display is a 3 charac ter window int o the DS335's input data queue that could be scr olled to view the prev ious 256 characters. The data is displayed in ASCII hex format, with each input character represent ed by 2 hex adecimal digits. The most recently received character has a decimal point indicator. Pressing [ DOWN A RROW] scrolls the display to the beginning of the queue, and [UP ARROW] s c r olls to later in the queue.

AUTO-TEST

Introduction The DS335 has a built-in test routine that allows the user to test a large

portion of instrument functionality quickly and easily. Self-test starts every time the DS335 is turned ON.

SELF-TEST The DS335's self-test is always executed on power-up. The test checks

most of the digital circuitry in the DS335, and should end with the display "test pass". If the self-test encounters a problem it will immediat ely stop and display a warning message. S ee the TROUBLES HOOTING section f or a list and explanation of the err or messages. If the DS335 fails its t est it still may be operated.

The DS335 tests its CPU and data memory, ROM program memory, calibration constant integrity, the computer interfaces, and the modulation program memory

Items not tested are the connections from the PC boards to the BNC connectors, the 12-bit waveform DAC, the output amplifier, the offset and amplitude control ci r c uits, and the output attenuators.

CALIBRATION BYTES It is possible to recall and modify the DS335 factory calibration bytes. P leas e

refer to the Test and Calibration Chapter for more detail.

DS335 Synthesized Function Generator

Programming Commands 3-1

PROGRAMMING THE DS335

The DS335 Function Generator may be remotely programmed via either the RS232 or GPIB (IEEE-488) interfaces. Any computer supporting either of these interfac es may be used to program the DS335. O nly one int erface is active at a time. All front and rear panel features (except power) may be controlled.

GPIB Communications The DS335 supports the IEEE-488.1 (1978) interface standard. It also

supports the required common commands of the IEEE-488.2 (1987) standard. Before attem pting to communicat e with the DS335 over the G PIB interface, the DS335's device address must be set. The address is set in the second line of the GPIB menu (type [SHIFT][1] twice), and may be set between 0 and 30. The default addres s is 22.

RS232 Communications The DS335 is c onfigured as a DCE (transmit on pin 3, r eceive on pin 2) and

supports CTS/DTR hardware handshaking. The CTS signal (pin 5) is an output indicating t hat t he DS335 is ready, while the DT R signal (pin 20) is an input that is used to control the DS335's transmitting. If desired, the handshake pins may be ignored and a sim ple 3 wire interfac e (pins 2, 3 and

7) may be used. The RS232 interf ace baud rate may be set in the second line of the RS232 menu (type [SHIFT][2] twice). The interface is fixed at 8 data bits, no parity, and 2 stop bits.

Front Panel LEDs To assist in progr amming, the DS335 has 4 front panel status LEDs. T he

RS232 and GPIB LEDs flash whenever a character is received or sent over the corresponding interface. The ERROR LED flashes when an error has been detected, such as an illegal command, or an out of range parameter. The REMOTE LED is lit whenever the DS 335 is in a rem ote state (front panel locked out).

Data Window To help find program errors, the DS335 has an input data window which

displays the data received over either the GPIB or RS232 interfaces. This window is activated by typing [SHIFT][2] or [SHIFT][1] three times. The menu displays the received data in hexadecimal format. The last 256 characters received can be scrolled through using the MODIFY up/down arrow keys. A decimal point indicates the most recently r eceived character.

Command Syntax Communications with the DS 335 use ASCII charact ers. Commands may be

in either UPPER or lower case and may contain any number of embedded space characters. A command to the DS335 consists of a four character command mnemonic, arguments if necessary, and a command terminator. The terminator may be either a carriage return <cr> or linefeed <lf> on RS232, or a linefeed <lf> or EOI on GPIB. No comm and processing occurs until a command term i nator is received. All commands f unc tion identically on GPIB and RS232. Command mnemonic s beginning with an asterisk "*" ar e IEEE-488.2 (1987) defined common commands. These commands also function identically on RS232. Commands may require one or more parameters. Mult iple par am eters are separated by commas "," .

Multiple commands may be sent on one command line by separating them by semicolons ";". The difference between sending several commands on the same line and sending several independent commands is that when a command line is parsed and exec uted the entire line is execut ed before any other device action proceeds.

DS335 Synthesized Function Generator

3-2 Programming Commands

There is no need to wait between commands. The DS335 has a 256 character input buf f er and processes c ommands in the order receiv ed. I f t he buffer fills up the DS335 will hold of f handshaking on the GPIB and attempt to hold off handshaking on RS232. If the buffer overflows the buffer will be cleared and an error reported. Similarly, the DS335 has a 256 character output buffer to store output until the host computer is ready to receive it. If the output buffer f ills up it is c leared and an error report ed. T he GPIB out put buffer may be cleared by us ing the Device Clear universal command.

The present value of a particular paramet er may be determined by querying the DS335 for its value. A query is formed by appending a quest ion mark " ?" to the command mnemonic and omitting the desired parameter from the command. If multiple queries are sent on one command line (separat ed by semicolons, of course) the answers will be returned in a single response line with the individual responses separated by semicolons. The default response terminator that the DS335 sends with any answer to a query is carriage return- linefeed <cr><lf> on RS232, and linefeed plus EOI on GPIB. All commands retur n integer results except as noted in individual com mand descriptions.

Examples of Command For m ats FREQ, 1000.0 <lf> Sets the frequency to 1000 Hz.

FREQ? <lf> Queries the frequenc y . *IDN? <lf> Queries the device identification (query, no

parameters). *TRG <lf> Tr igger s a s weep ( no parameters). FUNC 1 ;FUNC? <lf> Sets function to s quar e wav e( 1) then queries the

function.

Programming Errors The DS335 reports two types of errors that may occur during command

execution: command errors and execution errors. Command errors are errors in the command syntax. For example, unrecognized commands, illegal queries, lack of terminators, and non-numer ic ar gum ents are examples of command errors. Execution errors are errors that occur during the execution of syntactically correct commands. For example, out of range parameters and com mands that are illegal for a part icular mode of operation are classified as ex ec ution errors.

No Command Bit The NO COMMAND bit is a bit in the serial poll register that indic ates that

there are no commands waiting to be executed in the input queue. This bit is reset when a complete command is received in the input queue and is s et when all of the commands in the queue have been executed. This bit is useful in determining when all of the commands sent to the DS335 have been executed. This is convenient because some commands, such as setting the function or sweep, take a long time to execute and there is no other way of determining when t hey are done. The NO COMMAND bit may be read while commands are being executed by doing a GPIB serial poll. There is no way to read this bit over RS232. Note that using the *STB? query to read this bit will always return the value 0 because it will always return an answer while a command is executing- the *STB? command itself!

DETAILED COMMAND LIST The four letter mnemonic in each command sequence specifies the

command. The rest of the sequence consists of parameters. Multiple

DS335 Synthesized Function Generator

Programming Commands 3-3

parameters are s eparated by commas. Parameter s shown in { } are optional or may be queried while those not in {} are required. Commands that may be queried have a question mark in parentheses (?) after the mnemonic. Commands that may ONLY be queried have a ? after the mnemonic. Commands that MAY NOT be queried have no ?. Do not send ( ) or { } as part of the command.

All variables may be expressed in integer, floating point or exponential formats (i.e., the number five can be either 5, 5.0, or .5E 1). The var iables i and j usually take integer values, while the variable x take real number values.

Function Output Control Commands

AECL The AECL c ommand sets the output to the ECL levels of 1 V peak-to-peak

with a -1.3 V offset. That is, from -1.8V to -0.8V.

AMPL (?) x The AMPL command sets the output amplitude to x. The value x must

consist of the numeric al value and a units indicator. The units may be VP (Vpp) or VR (Vrms). For example, the command AMPL 1.00VR will set the output to 1.0 Vrms. Note that the peak A C voltage ( V pp/2) plus the DC offset voltage must be less than 5 Volts (for 50Ω source). Sett ing the amplitude to 0 Volts will produce a DC only (no AC function) output controlled by the OFFS command.

The AMPL? query will return the amplitude in t he currently displayed units. For example, if the display is 3.0 Vrms the AMPL? query will return 3.0VR. If a units indicator is sent with the AMPL? query (such as, AMPL? VP) the displayed units will be changed to match the units indicator and the amplitude returned in t hose units.

ATTL The ATTL command sets the TTL output levels of 5V peak-to-peak with a

2.5V offset. That is, f rom 0V to 5V.

FREQ (?) x The FREQ command sets the output frequency to x Hertz. The FREQ?

query returns the current output frequency. The frequency is set and returned with 1µHz resolut ion. If the current waveform is NOISE an er ror will be generated and the frequenc y will not be changed.

FUNC (?) i The F UNC command sets t he output function t ype to i. T he corr espondence

of i and function type is shown in the t able below. If the currently select ed frequency is incompatible with the selected function an error will be generated and the frequenc y will be set to t he maxim um allowed f or t he new function. The FUNC? query r eturns the current function.

i Function 0SINE 1SQUARE 2TRIANGLE 3RAMP 4 NOISE

INVT (?) i The INVT c ommand turns output inversion on ( i=1) and off (i= 0). The I NVT ?

query returns the current inversion status. This function is used with the ramp waveform to set it for pos itive or negative slope.

DS335 Synthesized Function Generator

3-4 Programming Commands

KEYS(?)i The KEYS command simulates the pressing of a front panel key. The

KEYS? query returns the keycode of the most recently pressed key. Keycodes are assigned as follows:

Key Name Key Code FREQ 1

AMPL 2 OFFSET 3 START FREQ 4 STOP FREQ 5 SWEEP RATE 6 0 7 18 29 310 Vrms/HZ/DOWN 11 SEL FNC 12 Decimal Point 13 414 515 616 Vpp/kHz/UP 17 +/- 19 720 821 922 MHz/SHIFT 23

OFF S (?) x The OFFS command sets the output's DC offset to x volts. The OFFS?

query returns t he current value of the DC offs et. The DC offset volt age plus the peak AC voltage must be less than 5 Volts (into 50Ω).

SYNC(?)I Turns the SYNC output on (i=1) or off (i=0). TERM(?) i Sets the output source impedance t o 50Ω (i=0), or hi-Z (i=1). The TERM?

query returns t he current source impedance sett ing. Note that all amplitude and offset display settings get doubled when switching f rom 50 Ohm to High Impedance. Similarly, when switching from high impedance to 50 Ohm all amplitude and offset display values get halved. The ac tual BNC output is not affected by this c hange.

Sweep & FSK Control Commands

note: All s weep & FSK parameters may be set at any time. For the changes to have an effect be sure that

the sweep or FSK type is set correctly and that sweep or FSK is enabled (see the STYP and SWEN commands).

FSEN(?) i Enables FSK on (i=1) or off (i=0). This funct ion is valid only if F SK has been

selected with the S DIR command ( S DIR2) or from the front panel. If the FSK rate has been set between 0.01Hz and 50 kHz then the FSK starts following the "FSEN1" command. If the rate has been set to 0Hz and FSK selected, the command "FSEN1" would enable the F SK BNC input on the rear panel. This TTL signal is sam pled at a 10MHz rate and toggles between the Start frequency and the Stop frequency.

DS335 Synthesized Function Generator

Programming Commands 3-5

*TRG The *TRG command triggers a s ingle s weep. The trigger sour c e must be set

to SINGLE (see the TSRC command below).

SDIR(?)i Sets the sweep direction. 0 = Ramp (unidirectional), 1 = Triangle

(bidirectional), 2 = enable FSK (disable sweeps).

STYP (?) i The STYP command sets the sweep type to i. The correspondenc e of i t o

type is shown in the table below. The STYP? query returns the current sweep type. Refer to the SDIR command for sweep direct ion.

i Waveform 0 LIN SWEEP 1 LOG SWEEP

SPFR (?) x The SPFR command sets the sweep stop f requency to x Hertz. A n error will

be generated if the sweep frequency is less than or equal to zero or greater than allowed by the current funct ion. The SPFR? query returns the current sweep stop frequency . If the stop frequency is les s than t he start frequency (the STFR command) a downward sweep from maximum to minimum frequency will be generated. The stop frequency is also used in the FSK mode.

SRAT (?) x The SRAT command sets the trigger rate for internally triggered single

sweeps and FSK to x Hertz. x is rounded to two significant digit s and may range from 0.01 Hz to 1 kHz for sweeps and 0.01Hz to 50kHz f or FSK. The SRAT? query returns t he current trigger rate. If the rate is set to 0Hz and FSK is enabled (SDIR = 2) then the external FSK BNC is used to toggle between the start and stop frequencies.

STFR (?) x The STFR command set s the sweep start f requency to x Hertz . An er ror will

be generated if the sweep frequency is less than or equal to zero or greater than allowed by the current function. The STFR? query returns the current sweep start frequency. If the start frequency is greater than the stop frequency (the SPFR command) a downward sweep from maximum to minimum frequency will be generated. T he stop frequency is also used in the FSK mode.

SWEN(?) i Enables sweeps on (i=1) or off (i=0). If the continuous sweep is selected,

enabling sweeps will start the sweep with the specified rate. If triggered single sweep is selected and s weeps ar e enabled then the DS335 waits for a front panel trigger or a *TRG command to start the sweep.

TSRC (?) i The TSRC command sets the trigger source for sweeps to i. The

correspondence of i to source is shown in the table below. The TSRC? query returns the current trigger source.

i Waveform 0 SINGLE 1 INTE RNA L RATE

For single sweeps t he *TRG comm and trigger s the sweep.

DS335 Synthesized Function Generator

3-6 Programming Commands

Setup Control Commands

*IDN? The *IDN common query returns the DS335's device configuration. This

string is in the format: StanfordResearchSystems,DS335,serial number,version number. Where "serial number" is the five digit serial number of the particular unit, and "version number" is the 3 digit firmware version number.

*RCL i The *RCL command recalls stored setting number i, where i may range from

0 to 9. If the stored setting is corrupt or has never been stored an execut ion error will be generated.

*RST The *RST common command resets the DS335 to its default configur ations. *SAV i The *SAV command saves the current instrument settings as setting number

Status Reporting Commands

(See tables at the end of the Prog rammin g section for Status Byte defini tion s.) *CLS The *CLS common command clears all status registers. This command

does not affect the st atus enable registers.

*ESE (?) i The *ESE command sets the standard event status byte enable register to

the decimal value i.

*ESR? {i} The *ESR common command reads the value of the standard event stat us

register. If the param eter i is present the value of bit i is returned (0 or 1). Reading this register will c lear it while reading bit i will clear just bit i.

*PSC (?) i The *PSC common command sets the value of the power-on st atus clear bit.

If i = 1 the power on status clear bit is set and all stat us registers and enable registers are cleared on power up. If i = 0 the bit is cleared and the stat us enable registers maintain their values at power down. This allows the production of a ser v ic e r eques t at power up.

*SRE (?) i The *SRE common command sets the serial poll enable register to the

decimal value of the param eter i.

*STB? {i} The *STB? common query reads the value of the serial poll byte. If the

parameter i is present the value of bit i is returned (0 or 1). Reading this register has no effect on its value as it is a summary of the other status registers.

DENA (?) i The DENA command sets the DDS status enable register to the decimal

value i.

STAT? {i} The STAT? query reads t he value of the DDS status byt e. If t he parameter i

is present the value of bit i is ret ur ned. Reading this regis ter will c lear it while reading bit i will clear just bit i.

DS335 Synthesized Function Generator

Programming Commands 3-7

Hardware Test and Calibration Commands

NOTE: These commands are primarily intended for factory calibration use and should never be needed during normal operation. In correct use of some of these commands can destro y the calibration of the DS335.

$CLK? The $CLK? command queries the DS335 for the status of its calibration

jumper. Shown below are the different status values that the DS335 can return:

Status value M eaning

0 Calibrat ion dis abled 1 Calibrat ion enabled

$FCL The $FCL command recalls t he factor y calibrat ion bytes . T his command will

generate an error if c alibr ation is not enabled.

*TST? The *TST? common query runs the DS335 int ernal self -tests. After the tests

are complete the test status is returned. The status may have the following values (see the TROUBLESHOOTING section for more details):

Status value M eaning

0 No Error. 1 CPU Er r or. The DS335 has detected a problem in its CPU. 2 Code Error. The DS335's ROM firmware has a checksum

error. 3 Sys RAM Error. The syst em RAM failed its test. 4 Cal Data Error. The DS335's calibration data has become

corrupt. 5 Unused. 6 Progr am Data Error. The modulation program RAM failed it s

test. 7 DS335 not warmed up. At least 2 minutes must elapse

between power on and calibration.

$PRE (?) i The $PRE command sets the DS335's pre-am plifier attenuators to range i.

The integer i is the attanuation value in dB and ranges from 0 to 14 in increments of two. Resetting the amplitude will return the attenuator s to their normal position. T he $PRE? quer y r eturns the current attenuator position.

$PST (?) i The $PST command sets the DS335's post-amplifier attenuat ors to range i.

The integer i is the attenuation value in dB and ranges from 0 to 30 in increments of two. Resetting the amplitude will return the attenuator s to their normal position. T he $PST? query returns the current attenuator position.

$WRD (?) j{,k} The $WRD command sets the value of calibrat ion word j to k. Parameter j

may have a value from 0 to 554, while k may range from -127 to +65535. This command will generat e an error if calibration is not enabled. NOTE: this command will alter the c alibration of the DS335. To correct the calibrat ion the factory calibrat ion byt es may be rec alled ( see the $F CL c ommand). T he calibration bytes cannot be altered unless t he warm- up bit has been set.

DS335 Synthesized Function Generator

3-8 Programming Commands

STATUS BYTE DEFINIT IONS

Status Reporting

The DS335 reports on its status by means of three st atus byt es: the serial poll byt e, the st andard status byte, and the DDS status byte.

On power on the DS335 may either clear all of it s status enable registers or maintain t hem in the state they were in on power down. The action taken is set by the *PSC command and allows things s uch as SRQ on power up.

Serial Poll Status Byte:

bit name 0 Sweep Done set when no sweeps are in progr es s 1 Sweep Enable set when sweep is enabled 2 User SRQ set if the user sends a SRQ from the front panel 3 DDS An unmask ed bit in the DDS status register has been set. 4 MAV The gpib output queue is non-empty 5 ESB An unmasked bit in the standard status byte has been set. 6 RQS/MSS SRQ ( S ervice Reques t)bit. 7 No Command There are no unexec uted commands in the input queue

The DDS and ESB bits are set whenever any unm asked bit (bit with t he corresponding bit in t he by te enable register set) in their respective status regis ters is set. They are not cleared until t he c ondition which set the bit is cleared. Thus, these bit s give a constant summary of the enabled status bits. A service request will be generated whenever an unmasked bit in t he serial poll register is set. Note that service request s ar e only produced when the bit is f irst set and thus any condition will only pr oduc e one servic e request. Accordingly, if a service request is desired ev er y time an event occurs the status bit must be cleared between events.

usage

Standard Event St atus Byt e:

bit name 0 unused 1 unused 2 Query E r r or Set on output queue overflow 3 unused 4 Execut ion err Set by an out of range parameter, or non-completion of some command due

5 Command err Set by a command syntax err or, or unr ec ogniz ed c ommand

usage

to a condition such as an incorr ec t waveform type.

DS335 Synthesized Function Generator

Programming Commands 3-9

6 URQ Set by any key press 7 PON Set by power on

This status byte is defined by IEEE-488.2 (1987) and is used primarily to report errors in commands received over the communications interfaces. The bits in this register stay set once set and are cleared by reading them or by the *CLS command.

DDS Status Byte:

bit name 0 Trig' d Set when a sweep is triggered. 1 Trig E r r or S et when a trigger rate error occurs . 2 Unused 3 Unused 4 Warm up Set after the warmup period has expired. 5 Test Error Set if a self t est error occurs. 6 Unused 7 mem err the stored setti ng wer e c or r upt on power up.

The Warmup bit will be set and remain s et after the warmup period has expired. T he rest of the bits in this register are set when t he corres ponding event oc curs and remain set until clear ed by reading this stat us byte or by the *CLS command.

usage

DS335 Synthesized Function Generator

3-10 Programming Commands

DS335 Synthesized Function Generator

Programming Examples 3-11

Program Examples

Introduction The following examples demonstrat e interfacing the DS335 via RS232 and

the GPIB interface using the National Instruments GPIB card. Using a different brand of card would be similar except for the program lines that actually send the data. These examples are intended to demonstrate the syntax of the DS335's comm and s et.

To successfully interface the DS335 to a PC via the GPIB interface, the instrument, interface card, and interface drivers must all be configured properly. To configure the DS335, the GPIB address must be set in the GPIB menu. The default GPIB address is 22; use this address unless a conflict occurs with other inst ruments in your system.

Make sure that you follow all the instructions for ins talling the GPIB card. The National Instruments card cannot be simply unpacked and put into your computer. To configure the car d you must set jumpers and switches on the card to set the I/O address and interrupt levels . You must run the program "IBCONF" t o configure the resident GP IB driver for your GPIB card. Please refer to the National Instruments manual for inf ormation. In this exam ple, the following options must be s et wit h IBCONF:

Device name: dds335 Device address: 22 EOS character: 0Ah ( linefeed)

Once all the hardware and GPIB drivers are configured, use "IBIC". This terminal emulation program allows you to send commands to the DS335 directly from your computer's keyboard. If you cannot talk t o the DS335 via "IBIC", then your pr ogr am s will not run.

Use the simple commands provided by National Instruments. Use "IBW RT " and "IBRD" to write and read from the DS335. After you are familiar with these simple commands, you can explore more complex programming commands.

The RS232 program ass umes the RS232 option is enabled ([ SHIFT][2] ) and the BAUD rate is set to 9600 BAUD.

The GPIB example was writt en in C and the RS232 example was writt en in BASIC.

DS335 Synthesized Function Generator

3-12 Programming Examples

EXAMPLE 1: GPIB COMMUNICATION. C LANGUAGE

This program communicates with the DS335 via GPIB . The program is written in C.

/* C Progr am to demonstrate comm unication with the DS335 via GPIB. Written in Microsoft C and uses National Instruments GPIB card. Assumes DS335 is installed as device name DDS335. Refer to National Instruments for Device Name setup. */

#include <stdio.h> #include <string.h> #include <stdlib.h> #include <dos.h>

#include <decl.h> /* National Instruments header files */ void main(void); /* function declaration */ int dds335; void main()

{ char cmd[ 40]; char star t[20]; char stop[20];

if ((dds335 = ibfind("DDS335")) < 0) /* open National driver */ { pr intf ("Cannot find DDS335\n"); exit(1); }

/* Now that the driver is located, reset the DS335 */ sprintf (cmd, "*RST\n");

ibwrt(dds335, cmd,strlen(cmd)); /* send command */ /* Setup the DS335 as follows:

500 kHz Square Wave, 1.5 Vpp, -1.0 Volt offset, display offset */ sprintf (cmd, "FREQ500000;AMPL1.5VP;OFFS-1.0;KEYS3;\n");

ibwrt(dds335, cmd,strlen(cmd)); /* send commands */ /* Now query the DS335 for the sweep start and stop frequencies */ sprintf (cmd, "STFR?\n"); /* ask for start rate */

ibwrt (dds335,cmd,strlen(cmd)); / * send query */ ibrd(dds335,st art,20); /* read back start frequency */

sprintf (cmd, "SPFR? \n "); /* ask for stop rate */ ibwrt (dds335,cmd,strlen(cmd)); / * send query */ ibrd(dds335,stop,20); /* read back stop frequenc y */

printf( "\n\n\n\n ******** DS335 Setup Demo *******" ); printf("\n\n\n\nDS335 Sweep Start Frequency = %e Hz\n\n", atof(start)); printf("DS335 Sweep Stop Frequency = %e Hz\n", atof(stop));

}

DS335 Synthesized Function Generator

Programming Examples 3-13

EXAMPLE 2: RS232 COMMUNICATION. BASIC LANGUAGE

BASIC Program to demonstrate communication with the DS335 via RS232. Program assumes the RS232 option is enabled (use [SHIFT] [2]) and the BAUD rate is set to 9600.

10 OPEN "com2: 9600,n,8,2,cs,ds,cd" FOR RANDOM AS #1 'Set up com2' 20 PRINT #1, " " 30 PRINT #1, "* r st" 'Reset the DS335' 40 GOSUB 190 'Query DS335 and diplay result' 50 PRINT #1, "f r eq1234567" 'Set new frequency' 60 GOSUB 190 'Query DS335 and diplay result' 70 PRINT #1, "* r st" 'Reset the DS335' 80 FOR I = 0 TO 4 'Step through all functions' 90 PRINT #1, "f unc", I 100 GOSUB 190 'Query DS335 and diplay result' 110 NEXT I 120 PRINT #1, "* r st" 'Reset the DS335' 130 PRINT #1, "am pl 0vp" 'Set amplitude to 0 volts ' 140 FOR I = - 5 TO 5 'Set DS335 offset from -5V to +5V' 150 PRINT #1, "offs", I 'and query each time' 160 GOSUB 190 'Query DS335 and diplay result' 170 NEXT I 180 END

'Routine to query the DS335 frequency,' 190 PRINT #1, "f req?" 'offset, and amplitude and display them' 200 INPUT #1, F 210 PRINT #1, "ampl?" 220 INPUT #1, A 230 PRINT #1, "offs?" 240 INPUT #1, O 250 PRINT " Frequ="; F; " Ampl="; A; " Offs="; O 260 RETURN

DS335 Synthesized Function Generator

3-14 Programming Examples

DS335 Synthesized Function Generator

Troubleshooting 4-1

TROUBLESHOOTING

If Nothing Happens on Power On Make sure that the power entry module on the rear panel is set for t he proper

ac line voltage for your location, that the correct fuse is inst alled, and that the line cord is inserted all t he way into the power entry module. The selected line voltage may be seen thr ough the clear window, just below the fuse.

When the unit is plugged in and turned "ON", the unit's firmware version number and serial number will be briefly displayed. Then the self tests should execute.

Cold Boot I f the unit displays no sensible message, the "cold boot " procedure may fix

the problem. To do a "cold boot ", turn the unit off. Then, while holding t he "+/-" button, turn the unit "ON". This procedure init ializ es the RAM and r ec alls all factory calibr ation values.

ERROR MESSAGES

Operational Errors These error messages may appear during normal f ront panel operation and

Message Meaning

AC Error Amplitude entered is out of allowable range. AC-DC Error The output |V

Freq Error At tem pt to set output frequency outside of range allowed f or curr ent f unction,

No GPIB Cannot access GPIB menus if opt ion board is not installed. No RS232 Cannot access RS232 menus if opt ion boar d is not ins talled. Off Error DC output offset outside of ±5V r ange ( into 50Ω). Out q err Output queue err or . The DS335 out put queue is full due to too many queries

The following lists explain all of the error messages that the DS335 can generate. The messages are divided into operational error s, errors in using the instrument , and self-test errors. The messages ar e lis ted alphabetically.

generally are warnings of illegal par am eter entries.

| + |Vdc| > 5V. Adjust either the offset or amplitude.

≤ 0 Hz or > 3.1 MHz, or attempting to set frequenc y for NOISE function.

that have not been read back. Range Er Parameter in command is out of allowed range for that command. Rate Err Sweep rate out of range (0.01 Hz to 1kHz). Rcl Err Paramet er memory corrupt on power up, stored setting cor rupt. Not a worry

unless this error occurs frequently. Check the battery if so. Span Err Logarit hmic sweep span er ror. The start and stop frequencies are apart by

more than six decades . StrtF Er T he s weep s tart frequency is out of range ( 0 < Freq ≤ max for function). Stop F Er The sweep stop frequency is out of range ( 0 < Freq ≤ max for function).

DS335 Synthesized Function Generator

4-2 Troubleshooting

Syn Err The command syntax is invalid. See PROGRAMMING section for correct

command syntax. UART Error The DS335 has detec ted an error on its computer interfac e option board. Uni Err The units s et wit h AMPL command are not V

, or V

rms

Self-Test Errors These errors may occur during the DS335's self- test. In general, these

messages indicate DS335 hardware problems. If the error s occur repeatedly

the unit may have an electrical problem. The messages are listed

alphabetically, also listed is the status value returned by the *TST?

command.

Message Status Value

Meaning

Cald Err 4 The RAM calibration data has become corrupt. The factory values will be

reloaded from ROM. This message is not a problem unless it occurs

frequently, whic h c ould indic ate a problem with the batter y backup c i r c uits. Code Err XX 2 The DS335's ROM has a checksum error. XX is the checksum value. CPU Error 1 The DS 335 has detected a problem in its Z80 CPU. Prgd Er r 6 Read/write test of modulation RAM (U400) failed. Can be bad RAM, ASIC,

or bus problem. Sysd Err 3 CPU RAM ( U206) failed read/write test. Cal Dly Err 7 T he DS335 is not warm ed up. Wait until warm ed up f or at leas t t wo m inutes

before starting autocal. GPIB PROBLEMS First, make sure that the GPIB interface is enabled. Press [SHIFT][1] to

display the enable stat us line. GPIB should be "ON". If not, turn G PIB on

using the UP/DOWN ARROW keys. Second, the GPIB address of the DS335

must be set to match that expected by the controlling comput er. The default

GPIB address is 22, and s o it is a good idea to use this address when writing

programs for the DS335. Any address from 0 to 30 may be set in the G PIB

menu. To check the GPIB address, press [SHIFT][1] twice t o view the GPIB

address. The entry keys or the UP/DOWN ARROW keys may be used t o s et

the GPIB address.

The DS335 will ignore its f ront panel key pad when Remote Enable (REN)

has been asserted by the GPIB. This "REMOTE" state is indicated by the

REMOTE LED. To return to LOCAL operat ion (ie. to enable the f ront panel)

press [3]. Controlling programs may inhibit the ability to return to LOCAL

operation by asserting the Local-Lockout state (LLO).

A linefeed character is sent with and End or Identify (EOI) to terminate

strings from the DS335. Be certain that your GPIB controller has been

configured to accept this sequence. RS-232 PROBLEMS First, make sure that the RS232 interface is enabled. Press [SHIFT][2] to

display the enable status line. RS232 should be "ON". If not, turn RS 232 on

using the UP/DOWN ARROW keys. Second, the RS -232 baud r ate mus t be

set to match that expected by the controlling computer . T he default baud

DS335 Synthesized Function Generator

Troubleshooting 4-3

rate is 9600 baud. The DS335 always s ends two stop bits, 8 data bits, and no parity, and will corr ectly receive data sent with eit her one or t wo stop bits.

When connecting to a PC, use a standard PC serial cable, not a "nullmodem" cable. The DS335 is a DCE (Data Communications Equipment) device, and so should be connect ed with a "straight" cable to a DTE dev ice (Data Terminal Equipment ). The "minimum" cable will pass pins 2, 3 and 7. For hardware handshaking, pins 5 and 20 (CTS and DTR) should be pas s ed. Occasionally, pins 6 and 8 (DSR and CD) will be needed: these lines are always asserted by the DS 335.

DS335 Synthesized Function Generator

4-4 Troubleshooting

DS335 Synthesized Function Generator

Performance Tests 4-5

PERFORMANCE TESTS

INTRODUCTION The procedures in this section test the performance of t he DS335. The first

set tests the basic functionality of the DS335 from the front panel. The second set of tests actually measures the DS335's specifications. The results of each test may be recorded on the test sheet at the end of this section.

NECESSARY EQUIPMENT The following equipment is nec essary to complet e the tests. The s uggested

equipment or its equivalent may be used.

Instrument Critical Specifications

Analog Oscilloscope 350 MHz B andwidth Tektr onix 2465 Time Interval Count er Frequency Range: 20 MHz minimum SRS SR620

Time Interval Accuracy: 1ns minimum

FFT Spectrum Analyzer Frequency Range: DC to 100 kHz SRS SR760

Amplitude Accurac y : ±0.2 dB Distortion: < 75 dB below ref er enc e

RF Spectrum Analyz er Frequency Range: 1 kHz to 100 MHz Anritsu MS2601/ HP4195A

Amplitude: ± 0.5 dB Distortion and Spurious : < -70 dB

DC/AC Voltmeter 5 1/2 Digit DC accuracy Fluke 8840A

True RMS AC to 100 kHz

Thermal Convert er Input Impedance: 50Ω Ballantine 1395A - 3

Input Voltage: 3 Vrms Frequency: DC to 10 MHz Accuracy: ±0.05dB

10 MHz Frequency Standar d Frequency: 10 MHz ± .001 ppm SRS FS 700

Phase Noise: < -130 dBc @ 100Hz

Recommended Model

50Ω Terminator 50Ω ± 0.2 %, 1 Watt HP 11048C Doubly Balanced Mixer Impedance: 50Ω Mini-Circ uits ZAD-3SH

Frequency: 1 - 20 MHz

DS335 Synthesized Function Generator

4-6 Performance Tests

FUNCTIONAL TESTS

These simple tests verify t hat the DS335's circ uitry is f unctional. T hey are not int ended t o verif y the DS335' s specifications.

Front Panel Test This t est v er ifies the functionality of the f r ont panel digit s , LED's, and buttons.

1) Turn on the DS335 while holding down [F REQ ]. Press t he [UP ARROW] and a single segment of the leftmost digit should light.

2) Use [DOWN ARROW] to light each segment (7 of them) and the decimal point of the left most t wo digits. Only a single segment should be on at a time. [UP ARROW] will step back war d through the pattern.

3) Push the down arrow key again and all of the segments of all 8 digits should light.

4) Pres s t he down arrow key repeatedly to light each front panel indicator LED in turn, top to bottom, left to right. At any time only a single LE D should be on.

5) After all of the LEDs have been lit further pressing of the front panel keys will display the key code associated with each key. Each key should have a different k eycode.

Internal Self-Tests The inter nal s elf tests test the functionalit y of the DS335 circuitry.

1) Turn on the DS335. The RO M firmware version number, and the s erial number should be displayed for about 3 seconds. The self tests will execute and the message "TEST PASS" should be displayed. If an error message appears see the TROUBLESHOOTING section for a description of t he errors.

Sine Wave This procedure visually checks the sine wave output for the correct frequency

and any visible irregularit ies .

1) Connect the DS335's output to the oscilloscope input and terminate in 50Ω.

2) Set the DS335 to s ine, 1 MHz, 10 Vpp, and 50Ω Load Impedance. S et the scope to 2 V/div vertic al, and .1us/div horizontal.

3) The scope should display a sine wave with one cycle per horizontal division and about five divisions peak-to-peak. There should be no visible irregularities in the waveform.

Square Wa v e This procedure checks the square wave output for frequency, rise time, and

aberrations.

1) Connect the DS335's output to the oscilloscope input and terminate in 50Ω.

2) Set the DS335 to square wave, 1 MHz, 10 Vpp, and 50Ω Load Impedance. Set the scope t o 2V/div v ertic al, and 200ns/div horizont al.

3) The scope should show two square waves about 5 division peak-topeak.

DS335 Synthesized Function Generator

Performance Tests 4-7

4) Increase the scope sensitivity to 1V/div and measure the size of the

overshoot at the beginning of t he square wave. It should be less than

0.2V peak-to-peak.

5) Adjust t he scope to 2V/div and 5ns/ div. Measure the 10% to 90% rise

time of the square wave. It s hould be les s than 20ns.

Amplitude Flatness This test provides a vis ual indic ation of the sine wave amplitude f latness.

1) Connect the DS335's output to the oscilloscope input and terminate in

50Ω.

2) Set the DS335 to s ine wave, 10Vpp, and 50Ω Load Impedance. Set to

linear sweep with a Unidirecti onal waveform. Set the st art frequency t o 1Hz, stop frequency t o 3MHz, and the rate to 100Hz. Turn t he DS335's sweep ON.

3) Set the scope to 2V/div vertical, and 1ms/div horizontal. Trigger the

scope on the falling edge of the DS335's SWEEP output (Rear Panel).

4) The scope should show a sweep that is essentially flat. The peak-to-

peak variations should be less than ±1.2%. Ignore any dc variations, using the peak-to-peak measurements for flat nes s c omparison.

Output Level This test pr ov ides a v is ual c hec k of the DS335' s output level control.

1) Connect the DS335's output to the oscilloscope input and terminate in

50Ω.

2) Set the DS335 to sine wave, 1MHz , 10Vpp, and 50Ω Load Impedance.

Set the scope to 2V/div vertic al and 1µs /div horizontal.

3) Verify that the DS335's out put is about 10V pk-to-pk.

4) Set the DS335 to 5Vpp verify the output.

5) Repeat step 4 at 1Vpp, 0.5 Vpp, 0.1 Vpp, and 0.05 Vpp. Adjust the

scope as necessary .

THIS COMPLETES THE FUNCTIONAL TESTS

DS335 Synthesized Function Generator

4-8 Performance Tests

PERFORMANCE TEST S

These tests are intended to measure the DS335's conformance to its published specifications. The test results may be recorded on t he test sheet at the end of this section. Allow the DS335 at least 1/2 hour to warm up, run the DS335's s elf t est pr oc edur e, and proceed with the tests.

FREQUENCY ACCURACY This test measures the accuracy of the DS335's frequenc y. If the fr equency

is out of specification the DS335's timebase frequency should be adjusted (see CALIBRATION section) .

Tolerance: ± 50 ppm of selected frequency

1) Turn the DS335 on and allow it t o warm up for at least 1/2 hour. Set the DS335 for sine wave, 1 MHz, 1 Vpp, and 50Ω Load Im pedanc e.

2) Attach the output of t he DS335 to the frequency counter. Term inate into 50Ω. Attach the reference frequency input of the counter to the frequency standard. Set the counter for a 1s frequency measur em ent.

3) The counter should read 1MHz ± 50Hz. Recor d the result.

AMPLITUDE ACCURACY The following tests measure the accuracy of the DS335 output amplitude.

There are separate tests for sine, square, and ramp/triangle. The tests measure the accuracy of the amplitude as a funct ion of frequency. The sine wave test also measures the performance of the attenuators. There is only a single test for triangle and ramp functions because they have the same signal path.

Frequency < 100 kHz Connect the DS 335 output to the voltmeter through the 50Ω terminator. Aft er

the DS335 has had at least 1/2 hour to war m up, per form the following tests.

Sine Wave specification: ±0.1 dB (±1.2%)

1) Set the DS335 to sine wave, 100Hz, 3.54 Vrms (10Vpp), and 50Ω Load Impedance.

2) Read the AC volt age on the voltmeter. Repeat at 1kHz and 10kHz, and 100 kHz. The readings should be between 3.498 and 3.582 Vrms (±1.2%) Record the results.

3) Set the DS335 to 1 kHz. Set the amplitude to 1 Vrms. Read the voltmeter and record the results. The amplitude should be between

0.988 and 1.012 Vrms. Repeat at 0.5 Vrms, 0.25 Vrms, 120 mVrms , 70 mVrms, 40 mVrms, and 20 mVrms. Recor d the result s. They should be within ±1.2% of the s et values .

Square Wave specification: ±1.2%

1) Set the DS335 to s quare wave, 100Hz, 5Vrms (10 Vpp), and 50Ω Load Impedance.

DS335 Synthesized Function Generator

Frequency > 100 kHz

Performance Tests 4-9

2) Read the AC voltage on the voltmeter. Repeat at 1 kHz and 10kHz. T he

readings should be between 4.94 and 5. 06 V rms. Triangle/Ramp Wav es specification: ±1.2%

1) Set the DS335 to triangle wave, 100Hz, 2.89Vrms (10 Vpp), and 50Ω

Load Impedance.

2) Read the AC voltage on the voltmeter. Repeat at 1 kHz and 10kHz. T he

readings should be between 2.85 and 2. 93 V rms.

Sine Waves specification: ±0.1 dB (±1.2%), frequency > 100k Hz

1) Connect the DS335's output to the thermal converter (because the

convertor has a 50Ω impedanc e no terminator is needed). Connect the

thermal converter output to the voltmeter using the most sensitive

voltmeter range since the nominal signal level is about 7mV DC. Allow

the DS335 at least 1/2 hour to warm up.

2) Set the DS335 to sine wave, 1 kHz, 3.00 Vrms, and 50Ω Load

Impedance. Allow the thermal converter 15 seconds to stabilize and

record the result as the 1k Hz reference value.

3) Step the DS335's f requency in 500kHz steps from 0Hz to 3. 1MHz. Allow

the thermal converter to stabilize at each frequency and record the

results.

4) Verify that the readings are within ±1.2 % of the 1 kHz reading for

frequencies above 1kHz. Square Waves specification: ±5%, frequency < 3.1MHz

1) Connect the DS335's output to the oscilloscope wit h a 50Ω terminator.

Set the DS335 to square wave, 1 kHz, 10Vpp, and 50Ω Load

Impedance. Set the scope t o 2V/div and 0.1ms/div.

2) Step the DS335's frequency in 100k Hz steps from 0k Hz to 3.1 MHz.

3) Verify that the DS335's output is within ±5% of the 1kHz amplitude.

DC OFFSET ACCURACY T his test measures the accuracy to the DS335' s DC off s et f unction.

DC Only

specification: 1.2% of setting ±.2mV

1) Connect the DS335's out put to the voltmeter with a 50Ω t erminat or. Set

the DS335 to 0.0V amplitude, and 50Ω Load Impedance.

DS335 Synthesized Function Generator

4-10 Performance Tests

DC+AC

2) Set t he DS335 t o 5V offset. Read the voltmeter and record the result. The result should be bet ween +4.94V and +5.06V.

3) Set the DS335 to -5V offset. Read the voltmeter and record t he result. The result should be bet ween -5.06V and -4.940V.

4) Set t he DS335 t o 0V offset. Read the voltmeter and record the result. The result should be bet ween -0.2 mV and +0.2mV.

specification: < ±80mV at full output

1) Connect the DS335's output to the voltm eter with a 50W term inator. Set the DS335 to sine wave, 1 kHz, 10Vpp, 0V offset, and 50Ω Load Impedance. Set the voltm eter to measure DC voltage.

2) Measure the offset voltage and verify that it is between -80mV and +80mV. Record the result .

3) Repeat step 2 at 100kHz, 1MHz, and 3.1MHz. Recor d the results and verify that the offset is between -80mV and +80mV at all of the frequencies.

SUBHARMONICS This test measures the subharmonic content of the DS335's sinewave

output. The frequencies in this test are picked such that spurious frequencies from the DDS process do not fall on the carrier posit ion.

specification: <-70 dBc

1) Connect the DS335 to the RF spectrum analyzer. Set the DS335 to sine wave,(10Vpp), 0V offset, and 50Ω Load Impedance.

2) Set the DS335 to 102 kHz. Set the s pectrum analyz er to 51 kHz cent er frequency, 10 kHz span. The carrier amplit ude at 51 kHz should be less than -70 dBc. Record the result.

3) Set the DS335 to 1.002 MHz, and the spectrum analyzer to 501 kHz. Measure and record t he amplitude of the 501 kHz carrier. It should be less that -70 dBc. Repeat f or 3.1MHz.

SPURIOUS SIGNALS These tests measure the spurious signals on the DS335's sine wav e outputs.

They check both close- in and wide band s pur s . specification: ≤ -65 dBc to 1MHz

≤ - 55 dB c to 3.1MHz

1) Connect the DS335 to the RF spectrum analyzer. Set the DS335 to sine wave,1Vpp, 0V offs et , and 50Ω Load Im pedanc e.

2) Set the DS 335 to 100 kHz. Set the spectrum analy zer to 100 kHz center frequency, 100 kHz span. Measure the amplit ude of the spurious signals and verify that t hey ar e ≤ -65 dBc. Increas e the span and c heck again.

3) Set the DS335 to 2 MHz. Set the spectr um analyzer to 2 MHz center frequency, 100 kHz span. Measure the amplit ude of the spurious signals and verify that t hey ar e ≤ -55 dBc. Increas e the span and c heck again.

DS335 Synthesized Function Generator

Performance Tests 4-11

HARMONIC DISTORTIO N This test measures the DS335's sine wav e harmonic dis tortion.

specification: ≤-60 dBc, frequency ≤ 100 kHz

≤ -50 dBc, frequency 0.1 to 1 MHz ≤ -40 dBc, frequency 1 to 3.1 MHz

1) Connect the DS335 output to the FFT analyzer input with a 50W

terminator. Set t he DS335 to sine wave, 100Hz, 1 Vpp, and 50Ω Load Impedance.

2) Adjust the FFT analyzer to view the fundamental and its harmonics.

Verify that all harmonics are below -60 dBc.

3) Repeat step 2 at 1 kHz and 10 kHz.

4) Connect t he DS335 output to the RF spectrum analyzer input . Set the

DS335 to 50 kHz. Verify that the harm onic s ar e at least -60 dBc.

5) Set the DS335 to 500 kHz, and 3 MHz, and verify that all harmonic s are

at least -50 dBc, and -40 dBc, res pec tively. Record the results.

PHASE NOISE This test measures the integrated phase noise of the DS335's output in a 15

kHz band about carrier. This test is performed at 1 MHz to minimize the contribution of discrete spurs to the measur em ent.

specification: < -60 dBc in a 30 kHz band centered about the carrier, exclusive of disc r ete spurious signals.

1) Set the DS335 to sine wave, 10.001 MHz, 1V rms.

2) Record the Phase noise reading f r om the FFT sc r een.

SQUARE WAVE RISE TIME This test measur es the r is e time and aber r ations of the square wave output.

specification: ris e time < 20 ns

overshoot < 2% of peak -to- peak output

1) Connect the output of the DS335 to the 350 MHz oscilloscope with a

50W terminator. Set the DS335 to square wave, 1 MHz, 10 Vpp, and 50Ω Load Impedance.

2) Set the oscilloscope to 2 V/div v ertical and 5 ns/div hor izontal. Meas ure

the time between the 10% and 90% points and verify that it is less t han 20ns. Record the results .

3) Set the oscilloscope to 1 V/div vert ical and 100 ns/div horizontal. Verify

that the overshoots and undershoots are less than ± 200 mV. Rec ord the results.

SQUARE WAVE SYMMETRY This test measures the symmetry of the squar e wav e output.

specification: < 1% of period + 3ns

1) Connect the output of the DS335 to the A input of the time interval

counter and term inate int o 50W. Set the DS335 to square wave, 1 MHz, 5 Vpp, and 50Ω Load Impedance.

DS335 Synthesized Function Generator

4-12 Performance Tests

2) Set the t ime int erval c ounter to measure t he positiv e width of the A input. Record the reading.

3) Set the time interval counter to measure the negative width of the A input. This reading should be equal to the reading in step 2 < ±13 ns. Record the result .

THIS COMPLETES THE PERFORMANCE TESTS

DS335 Synthesized Function Generator

DS335 PERFORMANCE TEST RECORD

Serial Number: __________ Dat e:____________ Tested By:______________

Comments:

Pass Fail

Functional Tests

Front Panel Test _____ _____ Self Test (at power up) _____ _____ Sine Wave _____ _____ Square Wave _____ _____ Amplitude Flatnes s _____ _____ Output Level _____ _____

Minimum Actual Maximum

Performance Tests 4-13

Performance Tests

Frequency Accuracy 999,950 Hz _________ ___ 1,000,050 Hz Amplitude Accurac y

sine, 100 Hz, 3.54 Vrm s 3.498 Vr m s ____________ 3.582 Vrms sine, 1 kHz, 3.54 Vrms 3.498 Vrms ____________ 3.582 Vrms sine, 10 kHz, 3.54 Vrms 3.498 Vrms ____________ 3.582 Vrms sine, 100 kHz, 3.54 Vr ms 3.498 Vrms ____________ 3.582 Vrms

sine, 1 kHz, 1 Vrms 0.988 Vrms ____________ 1.012 Vrms sine, 1 kHz, 0.5 Vrms 0.494 Vrms ____________ 0.506 Vrms sine, 1 kHz, 0.25 Vrms 0.247 Vrms ____________ 0.253 Vrms sine, 1 kHz, 120 mVrms 118 mVrms ____________ 122 mVrms sine, 1 kHz, 70 mVrms 69.1 mVrms ____________ 70.9 mVrms sine, 1 kHz, 40 mVrms 39.5 mVrms ____________ 40.5 mVrms sine, 1 kHz, 20 mVrms 19.7 mVrms ____________ 20.3 mVrms

square, 100 Hz, 5 Vrms 4.94 Vrms ____________ 5.06 Vrms square, 1 kHz, 5 Vrms 4. 94 V r m s ____________ 5.06 Vrms square, 10 kHz, 5 Vrms 4.94 Vrms ____________ 5.06 Vrms

triangle, 100 Hz,2.89 Vrms 2.85 Vrms ____________ 2.93 Vrms triangle, 1 kHz, 2. 89 V rms 2.85 Vr m s ____________ 2.93 Vrms triangle, 10 kHz, 2.89 Vrms 2.85 Vrms ____________ 2.93 Vrms

sine, 1 kHz, 3 Vrms referenc e = X ____________ Tolerance ±1. 2% of X ___________ __________

(0.980X) (1.020X) sine, 500 kHz, 3 Vrms ____________ sine, 1.0 MHz, 3 Vrms ____________ sine, 1.5 MHz, 3Vrms ____________ sine, 2.0 MHz, 3 Vrms ____________

DS335 Synthesized Function Generator

4-14 Performance Tests

sine, 2.5 MHz, 3 Vrms ____________ sine, 3.0 MHz, 3 Vrms ____________

square, 10 Vpp ____________ ___________

DC Offset Accuracy (DC only)

5.0 V 4.940 V _________ __ 5.060 V

-5.0 V -5.060 V ___________ - 4.940 V

0.0 V -0.0002 V ___________ 0.0002 V

DC Offset Accuracy (DC + AC)

1 kHz, 10 Vpp, 0 Vdc -0.08 V _________ __ 0.08 V 100 kHz, 10 Vpp, 0 Vdc -0.08 V ___________ 0. 08 V 1 MHz, 10 Vpp, 0 Vdc -0.08 V ___________ 0.08 V

3.1 MHz, 10 Vpp, 0 Vdc -0.08 V ___________ 0.08 V

Subharmonics

sine, 102 kHz,10 V pp ___________ -70dBc sine, 1.002 MHz,10 Vpp ___________ -70dBc sine, 3.1 MHz, 10 Vpp ___________ - 70dBc

Pass Fail

Spurious Signals

sine, 100 kHz ___________ -65 dBc sine, 2 MHz ___________ -55 dBc

Harmonic Distort ion

sine, 100 Hz, 1 Vpp ___________ -60 dBc sine, 1 kHz, 1 Vpp ___________ -60 dBc sine, 10 kHz, 1 Vpp ___________ -60 dBc sine, 50 kHz, 1 Vpp ___________ -60 dBc sine, 500 kHz, 1 Vpp ___________ -50 dBc sine, 1 MHz, 1 Vpp ___________ -50 dB c sine, 3.1 MHz, 1 Vpp ___________ -40 dBc

Phase Noise

noise ___________ -60 db

Square Wave Rise Time

square, 1 MHz, 10 Vpp. 10% to 90% rise t im e ___________ 18 ns square, 1 MHz, 10 Vpp. Overshoots ___________ ±200 mV

Square Wave Symmet ry

square, 1 MHz, 5 Vpp. + pulse width _________ __ square, 1 MHz, 5 Vpp. - pulse width ___________ asymmetry = (+ widt h) - (- width) ___________ 13 ns

DS335 Synthesized Function Generator

Calibration 4-15

CALIBRATION

Introduction The calibration of the DS335 is composed of two parts: adjustment and

calibration. Adjustments are actual physical adjust ment s to variable resist ors and capacitors to correct the DS335's filters, and out put amplifier response. Calibration is the process of determining the calibration constants ("calbytes") that the DS335 firmware uses to correct the output amplitude, etc..

The settings of the adjust ment s are, in general, very stable and s hould rarely require change. If the adjustments are changed the corresponding calibrations must be performed. However, the DS335 rarely requires complete recalibration to maintain its performance. It is recommended that the unit be sent back to the manufacturer in the case where a full recalibration is requir ed.

Calibration Enable The DS335 is shipped with calibration byte editing disabled. When

calibration is disabled, direct access to the calbytes is prevented. The internal calibration enabl e jumper must be set to enable calibration. To set the jumper remove the DS335's top cover by removing its four retaining screws (this will break the calibration seal). In the c enter of t he bottom circuit board is a three pin jumper labeled J P200. Setting JP200 between pins 1 and 2 enables calibration, setting it between pins 2 and 3 disables calibration.

Calbytes T he DS 335' s c alibr ation is controlled by calibr ation constants ("calby tes") that

the firmware us es to adjust the various output parameters. These calbytes are stored in the DS335's RAM. Recalibration of the DS335 involves determining the values of the calbytes and st oring the new values in RAM. The calbyte values at the time of the DS335's pr oduction are also stored in ROM and may be recalled at any time.

Direct access to the DS335's calbytes is allowed from both the front panel and computer interfaces after calibration is enabled. From the front panel press [SHIFT][9] once to display the calbyte menu line. There are two displayed parameters : on the left is the calbyte num ber, and on the right is the calbyte value. The calbyte number and value may be modified with either the keypad or the UP/DOWN ARROW keys. To select an item use the [SHIFT][DOWN ARROW] and [SHIFT][UP ARROW] keys. The calbyte number may be set between 0 and 554. The calbyte value may be set between -127 and 65536. The com plete set of factory calbyte values may be recalled by pressing [SHIFT][9] twice to bring up the Clear Cal menu and then pressing any of the unit keys. The tables on the following pages lists the DS335 calbytes. Shown is the calbyte number, name, and meaning.

DS335 Synthesized Function Generator

4-16 Calibration

DS335 CALBYTES

Number Name Meaning

0 OSC_FREQ Sets 10 MHz clock. 0 to 4095. Nom:2048 1 SINE_AMP L.F. Sine amplitude. 29,000 to 36,000. Nom:2^ 15. 2 SQ _A M P L.F. Square amplitude. 29,000 to 36,000. Nom:2^15. 3 TRI_AMP L.F. Triangle amplitude. 29,000 to 36,000. Nom :2^15. 4 RAMP_AMP L.F. Ramp amplitude. 29,000 to 36,000. Nom:2^15. 5 NOISE_AMP L.F. Noise amplitude. 29, 000 to 36,000. Nom:2^15.

6 OFF S _GAIN Adjusts gain for output offsets. 29k- 36k Nom:2^15 7 SW _OF F +/-127. Nom: 0. Value added to 12 bit Offset DAC. 8 0dB_OFF +/-127. Nom:0. Value added to 12 bit Offset DAC. 9 2dB_O FF +/-127. Nom:0. Value added to 12 bit Offset DAC. 10 4dB_OFF +/-127. Nom:0. Value added to 12 bit Offset DAC. 11 6dB_OFF +/-127. Nom:0. Value added to 12 bit Offset DAC. 12 8dB_OFF +/-127. Nom:0. Value added to 12 bit Offset DAC. 13 10dB_OFF +/-127. Nom:0. Value added to 12 bit Offset DAC. 14 12dB_OFF +/-127. Nom:0. Value added to 12 bit Offset DAC. 15 14dB_OFF +/-127. Nom:0. Value added to 12 bit Offset DAC.

Pre-attenuat or gain calibration values. Thes e v alues ar e linear in the measured gain for the pre-att enuator.

16 PRE_0dB Always set to 2^16-1 (65535). The reference gain. 17 PRE_2dB +/- 5% from nominal value of 52057. 18 PRE_4dB +/- 5% from nominal value of 41350. 19 PRE_6dB +/- 5% from nominal value of 32845. 20 PRE_8dB +/- 5% from nominal value of 26090. 21 PRE_10dB +/ - 5% fr om nominal value of 20724. 22 PRE_12dB +/ - 5% fr om nominal value of 16461. 23 PRE_14dB +/ - 5% fr om nominal value of 13076.

Post-att enuator gain calibrati on values. These values are linear in the measured gain for the post-amplifier attenuator. There are two of these tables corresponding to the measured gains in the 50 Ohm, and HighImpedance load conditions. These t ables compensate for att enuator er rors, finit e amplifier output resistance, internal 50 Ohm resistor tolerances, and reflec ts the fact that the output amplit ude of high- impedance loads is twice that of the 50 Ohm cases.

High Impedance table goes f irst, as its first entry is the r eferenc e gain for all other measurements :

24 HI_0dB Fix ed at 2^16-1 (65535). Referenc e gain lev el. 25 HI_2dB +/- 5% from nominal value of 52057. 26 HI_4dB + /- 5% from nominal value of 41350. 27 HI_6dB + /- 5% from nominal value of 32845. 28 HI_8dB +/- 5% from nominal value of 26090. 29 HI_10dB +/- 5% from nominal value of 20724. 30 HI_12dB +/- 5% from nominal value of 16461. 31 HI_14dB +/- 5% from nominal value of 13076. 32 HI_16dB +/- 5% from nominal value of 10386. 33 HI_18dB +/- 5% from nominal value of 8250. 34 HI_20dB +/- 5% from nominal value of 6553. 35 HI_22dB +/- 5% from nominal value of 5205. 36 HI_24dB +/- 5% from nominal value of 4135. 37 HI_26dB +/- 5% from nominal value of 3284. 38 HI_28dB +/- 5% from nominal value of 2609. 39 HI_30dB +/- 5% from nominal value of 2072.

DS335 Synthesized Function Generator

Now the post amplifier att enuator gains for 50 Ohm case:

40 50_0dB +/- 5% from nominal value of 32768 41 50_2dB +/- 5% from nominal value of 26028. 42 50_4dB +/- 5% from nominal value of 20675. 43 50_6dB +/- 5% from nominal value of 16422. 44 50_8dB +/- 5% from nominal value of 13045. 45 50_10dB +/- 5% from nominal value of 10362. 46 50_12dB +/- 5% from nominal value of 8230. 47 50_14dB +/- 5% from nominal value of 6538. 48 50_16dB +/- 5% from nominal value of 5193. 49 50_18dB +/- 5% from nominal value of 4125. 50 50_20dB +/- 5% from nominal value of 3276. 51 50_22dB +/- 5% from nominal value of 2602. 52 50_24dB +/- 5% from nominal value of 2067. 53 50_26dB +/- 5% from nominal value of 1642. 54 50_28dB +/- 5% from nominal value of 1304. 55 50_30dB +/- 5% from nominal value of 1036.

Spare calbytes ( unus ed) :

56 Unused 57 Unused 58 Unused 59 Unused 60 Unused 61 Unused 62 Unused 63 Unused 64 Unused 65 Unused 66 Unused 67 Unused 68 Unused 69 Unused 70 Unused 71 Unused

Calibration 4-17

The following three t ables have a length of 160 entries, and contain si ne and s quar e wave leveling values and squarewave symmetry values as a function of frequency .

72 SINE_0 Fixed at 127. This is the reference value for dc. 73 SINE_1 0 to 255. Nominal 127. For 19,531 to 39,062 Hz . 74 SINE_2 0 to 255. Nominal 127. For 39,063 to 58,593 Hz. : 231 SINE_159 0 to 255. Nominal 127. For 3105468 to 3125000 Hz .

The next table of 160 wor ds c ontains amplitude leveling data for square wav e outputs. This data is used to modify squarewave am plitude control values as a function of frequency (there is no hardware acc ommodation for amplitude leveling of squarewave sweeps.)

232 SQ_0 Fixed at 2^15 (32, 768). The dc reference level. 233 SQ_1 For 19,531 to 39,062 Hz. +/-10% from nominal. 234 SQ_2 For 39,063 to 58,593 Hz. +/-10% from nominal. : : 391 SQ_159 For 3105468 to 3125000 Hz. +/-10% from nominal.

DS335 Synthesized Function Generator

4-18 Calibration

The last table of 160 words c ontains sync symmetry values as a function of frequenc y when sines or s quares are selected. T here are three values which precede the table: these are used to control the sync duty cycle for triangles, ramps, and noise.

392 TRI_SY M Triangle sync symmetry.0 to 4095. Nominal 2048. 393 RAMP_SYM Ramp sync symmet ry. 0 to 4095. Nominal 2048. 394 NOISE_SYM Noise sync duty . 0 t o 4095. Nominal 2048 395 SYM_0 0 t o 4095. Nominal 2048. For dc to 19530 Hz. 396 SYM_1 0 t o 4095. Nominal 2048. For 19,531 to 39,062 Hz. 397 SYM_2 0 t o 4095. Nominal 2048. For 39,063 to 58,593 Hz. : : : 554 SYM_159 0 to 4095. Nominal 2048. For 3105468 to 3125000 Hz.

DS335 Synthesized Function Generator

Calibration 4-19

NECESSARY EQUIPMENT The following equipment is necessary to complete the adjustments and

calibrations. The suggested equipment or its equivalent may be used.

Instrument Critical Specificat ions Recommended Model

Analog Oscilloscope 350 MHz Bandwidth Tektronix 2465 Time Interval Count er Frequency Range: 20 MHz min. SRS S R620

Time Interval Accuracy: 1ns max

FFT Spectrum Analyzer Frequency Range: DC to 100 kHz S RS S R760

Amplitude Accurac y : ±0.2 dB Distortion: < 75 dB below ref er enc e

RF Spectrum Analyz er Frequency Range: 1 kHz to 100 MHz Anritsu MS 2601/ HP4195A

Amplitude: ± 0.5 dB Distortion and Spurious : < -70 dB

DC/AC Voltmeter 51/ 2 Digit DC accuracy Fluk e 8840A

True RMS AC to 100 kHz

Thermal Convert er Input Impedance: 50 Ω Ballantine 1395A - 3

Input Voltage: 3 Vrms Frequency: DC to 10 MHz Accuracy: ±0.05dB

10 MHz Frequency Standar d Frequency: 10 MHz ± .001 ppm SRS FS700

Phase Noise: < -130 dBc @ 100Hz

50 W Terminator 50 Ω ± 0.2 %, 1 Watt HP 11048C

ADJUSTMENTS

Output Amplifier Bandwidth These adjustments correct t he bandwidth of the output amplifier . A c om plete

The following adjustment s set t he values of all of the var iable c omponents in the DS335. After an adjustment has been made the ass ociated calibrations must be made. All adjustments must be complete before calibration is started. First , remove the DS335's top cover by removing the four retaining screws.) Set the "cal enable" jumper ( JP200 switch 2) between pins 1 and 2.

NOTE: The chassis ground and circuit ground float relative to each other. For voltage measurements use the FUNCTION output BNC shield as a ground reference.

calibration must be per formed if these adjustments are changed. All of the adjustments are on the bottom PCB. Use an insulated adjusting scr ewdr iv er .

1) Connect the output of the DS335 to the oscilloscope with a 50W terminator. Set the DS335 to square wave, 8 Vpp, 100 Hz. Set the scope to 2 V/div vertical and 5 ms/div horizontal. Adjust R703 for the squarest output waveform.

2) Set the scope to 200ns/ div. Adjust C707 for the fastest output risetime without excessive overshoots.

3) Do a complete calibration of the DS335

DS335 Synthesized Function Generator

4-20 Calibration

Bessel Filter Adju stment This adjustment sets the bandpass of the DS335's Bessel waveform filt er .

1) Set the DS335 to RAMP wav eform, 8 Vpp, 10 kHz frequency. Connect the DS335's output to an oscilloscope with a 50W terminator. Set the DS335 for 50Ω Load Im pedance. Set the scope to 2 V/div vertical and 200 ns/div horizontal.

2) Adjust C542 to make the output rise time as fast as possible while minimizing the peak-to-peak ripple.

CALIBRATION

Clock Calibratio n This procedure sets the frequency of the DS335's internal 10 MHz clock.

The DS335 is fully calibrated at the f actory wit h all calibration bytes secur ed in ROM and RAM. The user can change the calibr ation bytes in RAM aft er changing the position of t he calibration jumper JP200. The list of calibrat ion bytes on page 6-2 shows the address and function of every byte. The only calibration byte that might need adjustment as the instrument ages is the frequency reference byte. The following procedure des cribes the adjustment of the DS335's clock calibr ation calbyte. In t he case where the calibr ation bytes in RAM get corr upted, the user can recall the factor y calibrat ion byt es. Please refer t o page 6-1 for that pr oc edur e.

Allow the DS335 at least 1/2 hour warmup before beginning calibration. All calibrations should be done with the DS335 c ompletely assembled and 1/2 hour of warmup after reassembly. When the new calbyte values are determined they s hould be entered into the DS335's RAM.

The procedure is identical for standard and optional oscillators. Be sure that the DS335 has been completely reassembled and war med up for at least 1/ 2 hour before this calibr ation is started.

1) Connect the DS335's Function output to the frequency counter input wit h a 50W terminator. Use the frequency standard as the counter's timebase.

2) Adjust the value of calbyt e 0 so that the frequency is within 1 Hz of 10 MHz (0.01 Hz for optional oscillators). The range of calbyte 0 is 0 to

4095.

DS335 Synthesized Function Generator

Circuitry 5-1

DS335 Circuit Description

Front Panel (DS3350FP )

The front panel pcb has 8 seven-segment displays, 26 LED indicators, and 22 keys. The displays are refreshed by a time multiplexing: there are four strobe lines which enable two digits, a column of sev en LEDs, and six keys.

The display refres h is synchronized by the Real-Time I nterrupt (RTI). The RTI occurs at a 500 Hz r ate. The display refresh is the first task in the RTI routine, so as to avoid display flicker. Five RTI's are required to refresh the entire display: four to refresh all of the displays and indicat ors and to look for k ey contacts, and a fifth to intensify a particular digit in the eight digit dis play .

Each LED and display has a 1:5 duty cycle. When intensified, the selected display will have a 2:5 duty cycle, making that digit twice as bright. T he intensity of the selected digit will blink between 1: 5 and 2:5 duty cycle at a 1 Hz rate.

Microprocesso r ( DS 335M 1)

The CPU is a CMOS Z80 (TMPZ84C00AP, U100) c loc k ed at 5 MHz. The CPU' s 64k mem ory spac e is divided in two: the lower 32k is occupied by a CMOS ROM (27256, U104), the top 32k has a battery backed-up CMOS RAM (HM62256LP, U105).

All other devices in the system are mapped as I/O. I/O port strobes (active low) are provided by the 1:16 decoder (74HC154, U108). Port strobes are separated by eight addr esses, leaving room to access r egisters within particular devic es .

Address/Name/Definition 00 -CS_8253 CS to RD or WR to 8253 triple counter/timer

08 -LED_STB WR to assert display strobe and speak er enable 10 -LED_EVEN WR for segment enables for EVEN display digits 18 -LED_ODD WR for segment enables for ODD display digit s 20 -LED_LAMP WR for LED indicator enables 28 -KEY_RD RD to read keypad matrix 30 -DAC_MPX WR to select channel for system DAC (and 4 LSB's ) 38 -DAC_STB WR for 8 MSB's to 12 bit system DAC 40 -RLY_CTL WR to set position of 7 system relays 48 -ASIC_CTL WR to set state of ASIC contr ol lines 50 -ASIC_WR WR to strobe opcodes and data into ASIC 58 -MOD_RAM CS to RD or WR to modulation RAM 60 -CMD_STB Command strobe to GPIB/RS 232 interface 68 DATA_CLK Serial data clock to RD/WR to inter face 70 -MISC_IN RD eight bit port of miscellaneous inputs 78 -MISC_OUT WR eight bit port of misc ellaneous outputs

Timing A 10 MHz crystal oscillator is the source of all timing. This oscillator is on page DS335M5, close to the

waveform DAC. For the DDS to work well, it is im perativ e that this clock be kept clean: henc e the oscillat or is operated from a separate s upply (+5_CLO CK) and it s output is passed direc tly to the wavef orm DAC. The 10 MHz is buffered to pr ov ide c loc k s to the rest of t he system.

DS335 Synthesized Function Generator

5-2 Circuitry

There is a TCXO option for the 10 MHz cloc k. When pr es ent, the TCXO may be tuned to exactly 10 M Hz . The frequency is calibrated by altering the constant used to compute the PIR value for the ASIC phase accumulator.

The buffered 10 MHz is divided by two by a D-type flip-flop (74HC74, U101A) t o provide a 5 MHz clock to t he CPU. A second flip-flop (U101B) divides the 5 MHz by two to provide a 2.5 MHz clock to the 8253 counter/timer, and to the UART and GPIB controller on t he communic ations interface board.

The 8253 provides three additional clocks by dividing its 2. 5 MHz input : a 500 Hz RTI is generated by dividing by 5000, a 1 kHz tone for the speaker is gener ated by dividing by 2500, and a 16x clock for 9600 baud is generated by dividing by 16 (whic h will hav e a 1.7% error).

Communications I nterface Header An 18 pin header to the optional GPI B/RS232 int erf ace is shown on sheet DS335FP. The computer int erf ace

must be ground referenced, while the function gener ator (and so its CPU, etc.) must float. To accommodate this, communications between the CPU and the interface are done serially, via opto-isolators. Data and commands are shifted t o and from t he interf ace with the port-s trobe "DAT A_CLK". Commands are executed (a register read, for example) when the port strobe "- CM D_STB " is as s erted.

A separate, ground referenced power supply is generat ed on the interface PCB by rectifying and regulat ing the 9 Vac which is supplied to the header .

GPIB and RS232 interrupts can assert the maskable interrupt to the Z80. If no interface is present, this interrupt will not be as serted. The CPU tests for the presence of the inter face on power-up by shifting data though the interface and looking for its return (with a 16 cycle delay, of course).

Data to the interfac e is buffered by a D-type flip-f lop, (74HC74, U107A ). The MSB of the data bus is clocked into the flip-f lop on the leading edge of the DATA_CLK, and clocked into t he interfac e's shift regist er on the trailing edge of the DATA_CLK . This is done t o eliminate proc essor nois e on the ribbon c able when t here are no communications. A byte is transferred to the interf ac e with eight outputs and eight left- s hift instructions.

Battery Back-up The contents of the 32Kx8 CMO S RAM are preserved when t he power is turned of f by a Lit hium batt ery. T he

CS to the RAM is disabled on power down by the -RESET, which turns off the NPN transistor (Q101, a 2N3904).

Display Driver ( DS335M2)

The front panel display is t ime multiplexed: two digits , and seven indicat ors may be refreshed, and six keys read during each of four successive strobe periods.

To refresh a part of the front panel display, one STROBE column is pulled high by writing a zero to the corresponding position in the LED_STB latch (U203, a 74HC374). For example, writing a zero to Q0 will saturate the PNP transis tor Q200, and pull STROBE_0 to +5 volts.

Digit segments and LED indicators within a particular STROBE column are turned on by wr iting a zero to the corresponding position in the LED_EVEN, LED_ODD, or LED_LAMP latches (U200-201, 74HC374's). For example, writing a zero to Q0 of the LED_EVEN latch will cause the 'a' segment of the 'even' digit display in the selected strobe column to turn 'on'.

There is a watch-dog circuit ( U111, D200, C200, and R229) which will turn off the f ront panel displays if the processor stops refreshing the LED_STROBE latch. The circuit pumps char ge onto C200 wit h every output to the LED_STROBE latch. C200 is discharged by R229 if the port strobes c ease, removing the out put enable from the 74HC374 display driver s .

DS335 Synthesized Function Generator

Circuitry 5-3

System DAC and S/H's (DS335M3)

There are four analog v oltages which may be set by the CPU. These four v oltages control the output s quare wave symmetry, square wav e am plitude, output offset, and wavef orm amplitude.

These analog voltages are on sample and hold amplifiers which are maintained by a 12 bit system DAC (U303, an AD7845). The DAC can output voltages from -5.00 to +5. 00V with input values from 0 to 4095.

To refresh a particular sample and hold, the analog mult iplexer (U304, a 74HC4051) is inhibited by writing a 'one' to the MSB (Q8) of the DAC_MPX latch ( U305, a 74HC273). Next, the address of the desired S/H is written to bits Q5, Q6 and Q7 of the DAC_MPX latch, along with the four LSB 's of t he desired 12 bit DAC value to Q1-4. Then the 8 MSB's of the 12 bit DAC value is writt en along with the port strobe -DAC_STB to load the 12 bit value int o the DAC. Finally , the inhibit to the DAC multiplexer is rem oved by writing a zero to the MSB (Q8) of the DAC_MPX latch.

A different sample and hold is r efreshed with each new RTI. The refresh int er val is two milliseconds. The square wave symmetry control voltage may be set over +/-5V with zero being nominal. This voltage

controls the duty cycle of the SYNC and square wave outputs, and varies with frequency to maintain the output at 50% duty cycle per the contents of a calibration t able.

The square wave amplitude c ontr ol voltage may be set over + /-5V. The act ual out put s quare wave amplitude is linear in the DAC value, and z er o when the DAC value is zer o. This voltage is set to -5V if a square wave is not selected in order to reduce cross-talk in the function select relay.

The output offset cont rol voltage may be set over the range of -10.5 t o +10.5V. T he higher output levels ar e due to the gain of x2.1 of the sample and hold amplifier for this control voltage. The front panel function output will have an dc offset equal to t his control voltage. Calibrat ion values will off set and gain-cor rect this control voltage so that the actual output offset equals that s et f r om t he front panel.

The waveform amplitude cont rol sample and hold output is level shifted and attenuat ed to a +3 to +5 Vdc range. This cont rol voltage is used as a referenc e to the 8-bit amplitude leveling DAC, which is cont rolled by the ASIC during frequenc y s weeps . The the weighted sum of the leveling DAC output and amplitude control voltage is scaled to the range of -.75 to -1.25 for the nominal leveling DAC v alue of 128.

DDS ASIC (DS335M4)

Waveforms are generat ed in the DS335 by updat ing a 12 bit DAC at a rate of 10 million sam ples per second. The waveform (sine, ramp, saw, or noise) is stored in ROM, and the ROM is addressed by a 'phase accumulator' which is im plem ented in a CMOS ASIC.

The ASIC's phase accum ulator is a 48 bit adder, with the top 15 bits of t he ac cumulated result s erving as t he address to the ROM. The frequency of the output waveform is proportional to the rate at which ROM addresses change, s o, the larger the number added to the phase accumulator t he higher the frequency. The 48 bit number resides in six 8-bit registers in the ASIC. This 48-bit number is called the 'phase increment register', or PIR.

To facilitate seamless frequency changes, there are two phase increment registers, PIRA and PIRB. The adder will use one of the PIR's while t he host processor (or modulation RAM ) is writ ing to t he other, and t he adder can shift between the two PIR's without missing a single add cycle.

In addition to the PIR' s, there are lots of other registers in t he ASIC. The other regist ers are us ed for mode control, setting pr escalers, and setting modulation ( sweep) addresses. Three of these regis ters, are located off the ASIC: strobes ar e generat ed which will allow modulat ion data to be latc hed int o external devices. This allows amplitude leveling during sweeps, etc., by the modulation program . The FSK BNC input goes directly to the ASIC and allows the user t o select between PIRA and PIRB by changing the input level.

DS335 Synthesized Function Generator

5-4 Circuitry

To set an output frequency, Fout, the PIR is set to: PIR = Fout x 2^48 / Fclk

where Fclk is the 10 MHz ASIC clock. Math oper ations t o compute the PIR must be done to 48 bit pr ecision, so, a 48x48 bit multiply is required t o compute a PIR value.

The ASIC register s are loaded by providing an op-code ( which t ells which and how many regist ers to load ) and data ( which is loaded into t he target registers ). These op- codes and data may be provided direc tly by the CPU after a -HOST_REQ is issued and a HOST_A CK received. Or, a series of op-codes and data may be stored in the 32K x 8 modulation RAM ( U400, a 62256). T he modulation RAM is used to store dat a for frequency sweeps. Sweeps can consist of up to 4000 different frequencies together wit h amplitude leveling data.

The modulation RAM is addr essed by the ASI C. To load modulation op-codes and data, the st art address f or the modulation program is writ ten to the ASIC's MODSTRT register s, and loaded into t he modulat ion address counters. Op-c odes and data are written s equentially to the modulat ion RAM as outputs to -MOD_RA M port. The -MOD_RAM port strobe writes data to the modulation RAM and incr em ents the modulation address.

There is one eight-bit DAC which is loaded as if it were an ASIC register. The DAC (U402, a AD7524) controls the reference voltage to the waveform DAC, and so the output amplitude. DAC values from 0 to 255 control the reference from minus 0.75 to minus 1.25 Vdc. This DAC is used to level the output amplitude during frequency sweeps .

There is a 74HC273 (U413) t hat is also loaded as if it were an ASIC register; its output goes directly to the SWEEP/FSK rear panel BNC. When t he DS335 is performing a sweep, this output provides a puls e that is synchronous with the sweep rate. When the DS335 is performing internal FSK, the SWEEP/FSK ouptut voltage toggles at the FSK rate.

The waveform addresses gener ated by the ASIC access one of four 8k long tables in wav eform ROMs (U409, U411). These tables contain sine, ramp, saw and noise data. The tables ar e selected by the two MSB ’s of the ASIC_CTL latch, (U404, a 74HC273). Data from the ROMs is latched into two 8-bit latches (U410 and U412, 74F374's).

Waveform DAC (DS335M 5)

Latched waveform data (WD0 to WD11) is filtered by 470 Ohm resistor networks before being latched into the 12-bit waveform DAC (U500, a TDC1012) by the rising edge of the 10 MHz CONV clock. The differential current outputs from the DAC have a range from 0 to -40 mA:

Value +OUT -OUT 0 0 -40.000 mA

1 -.01 -39.990 7FF -19. 995 -20.005 800 -20.005 -19.995 FFE -39.990 -00.010 FFF -40.000 0

Because the DAC outputs can only sink current, part of the output termination network is connected to a positive voltage sour ce which t racks t he DAC reference input. This arrangem ent keeps both outputs c entered on 0 Vdc. This improves the per formance of the DAC and eliminates any dc curr ent f r om the output filters.

DS335 Synthesized Function Generator

Circuitry 5-5

Output Filt ers ( DS335M5)

There are two output f ilter types: a Bessel filter and a Cauer filt er . Both filter s have a charac teristic impedance of 50 Ohms: they are driv en by, and t erminated into 50 Ohms. The f ilters are different ial filters: they hav e complementary inputs and outputs, and are closely phase matc hed between the inputs because they share the same physical core.

The Bessel filt er is a 5t h degree filter with the -3 dB point set to 3.5 MHz. This filter is used when ramps, triangles or noise func tions are selected. T he Bessel filter has excellent phase-linear response so t hat there will be no overshoot or ringing of the output waveform.

The Cauer filter is a 7t h degree filter with a passband to 3.4 MHz and a stopband attenuation of 86 dB. The Cauer filter is used when s ines or square wave output s are selected. Cauer filt ers provide steep roll-offs and flat passband characteristics.

A Sin(x)/x compens ator pr ecedes the Cauer f ilter. This cir cuit compens ates for t he reduced signal level of t he sampled waveform as the frequency of the output approaches the Nyquist limit. The circuit increases the amplitude to compensat e for t he effect by increas ing t he ter mination impedanc e of the DAC out put f or higher frequencies.

A pair of DPDT relays (U501 and U502, HS -212's) select between t he Bessel and Cauer f ilters. T hese relays are controlled by the LS B of the -RELAY _CTL latch (U800, a 74HC374) and ar e driven by an em itter- follower (U801, a CA3082).

Pre-attenu ator ( DS 335M 5)

The output from the selected filter is terminated by a 0 to 14 dB resistive differential attenuator. This attenuator must be us ed when an output offset other than zero is selec ted. (The peak ac amplitude plus offset must not exceed 10 V at the output of the amplifier.) The attenuator will also be us ed for outputs of less that

0.3 Vpp. A pair of 1:8 analog multiplexers (U600 and U604, 74HC4051's) select the attenuation factor in 2 dB steps.

The analog multiplexers are controlled by the -MISC_OUT latch (U109, a 74HC273). The multiplexers are inhibited by SQ/- SI NE if a square wave output is selected. This will reduce crosstalk in the function select relay (U603, a HS-212) .

SYNC Generator (DS335M 6)

The un-attenuat ed signal from the filters is buffered by emitter followers (Q600 and Q602, 2N3904's). T he buffered diff erential signal drives a differential c ompar ator (U601, an AD9696) t o generate a SYNC s ignal. The positive feedback provides lots of hysterisis, and additional resistive feedback to the emitter followers cancels the kick - bac k fr om the c om parator.

The comparator output is buffered by an octal driv er (U602, a 74HC244) which has sev en of it s outputs wire in parallel to drive the f ront panel SYNC out put. T he SYNC output is driven t hough a 47 Ohm resistor provide reverse term ination of reflected pulses.

The comparator also drives a pnp differential pair (Q603 and Q604, 2N3906's) to generate a differential square wave at their collectors. The amplitude of the square wave is controlled by the analog voltage, SW_AMPL, which cont rols the pnp constant current sourc e (Q601, a 2N3906). The externally compensat ed op-amp (U605, a CA3140) m aintains a voltage across the emitter res is tor which is proportional to (SW_AMPL + 5.00Vdc). As SW_AMPL varies from -5 to +5V, the constant current source varies from 0 to 11 mA, generating from 0 to 1.1 Vpp square wave output.

DS335 Synthesized Function Generator

5-6 Circuitry

Function Select io n (DS 335M 6)

The DPDT relay (U603, an HS212) selects between the filtered (and perhaps attenuated) waveform DAC output, and the output of the square wave generator . If the square wave output is not being used, then t he square wave amplitude will be set to zero (SW_AMPL=-5 Vdc) so as to reduce cr os s talk in the f unc tion select relay. The selected function is passed to the differ ential output amplifier.

Output Amplifier ( DS 335M 7)

The output amplif ier is a high speed, low distortion, disc rete transistor differential amplif ier. The gain is x-10 for the inverting input, and x12 for the non- inverting input, and t he 3 dB bandwidth is 35 MHz, it has a phase linear response to about 175 MHz, and a THD of about 0.05% to 50 kHz. The am plifier has a very low offs et drift, as its dc characteristics are stabilized by an external compensated op- am p.

The amplifier has a very symmetric design. This, together with it class A operation and high open loop bandwidth, keeps it distortion very low. In this circuit description, only the 'top-half' will be desc ribed, as the 'bottom-half ' of t he am plifier operates in a completely s ymm etric al and c om plim entary manner.

The signal is applied to t he input different ial pair (Q701 and Q702, 2N5770's). The input pair r un in a constant current configuration, with the const ant current source (Q706 with R741 and D701). The pnp t r ans istor (Q700) provides an ac current to absorb the feedback current from R705. Since the input differential pair runs at constant curr ent, independent of the input signal, their base-emitter voltages are c onstant, and so are not a source of distort ion.

To understand the operation of the amplifier, consider events when a positive input signal is applied. The base of Q701 goes up, while Q702's base goes down. This increases Q701's collec tor current, pulling down the base of the emitter follower, Q709, which pulls the base of Q710 and Q711 down, increasing their collector current s. This current will cause t he collector voltage of Q710 to slew very quickly, and with lots of gain, because the collector load is a very high impedance. The Darlington pair, Q712 and Q713, buffer this node to drive the output, which is a 100 Ohm load. The current imbalance at the high impedance node will cause the output to continue to slew until the feedback current (though R703 and R747) brings the input differential pair bac k into balance.

The ac gain is adjusted by sett ing R703. The ac gain is adjusted to m atch the dc gain (which is controlled by the op-amp and its feedback resistor network.) The ac gain is determined by the ratio of the feedback resistors to the emitter resistors.

The op-amp (U700, a CA3140) and its feedback resistors (R700,701,702 and R723) stabilize the dc characterist ics. The op-amp is ext ernally com pensated s o that it will only corr ect low frequenc y errors, and so will not affect high fr equency perfor mance. The output of U700 is buff ered (for extra current dr ive) by U701A and U701B.

Output Attenuator ( DS 335M 8)

The output attenuator is a relay c ontrolled, 50 Ohm attenuat or, which allows at tenuat ion in a binary sequenc e of 2 dB steps. When the power is rem oved (or on RESET) all of the attenuat ors are switched 'in'. T he relays are controlled by bits written to the 8 bit latc h, U800, a 74HC273. Outputs from the latch are buffered by npn emitter followers (U801, a CA3082), which drive the relay coils . Each 2 dB attenuator can reduce the output by a factor of 0.794. Output levels between these steps are obt ained by adjust ing the referenc e level to t he waveform DAC. The total att enuation is 30 dB, or a factor of 0.0316, which will reduc e the 7. 94 Vpp level f r om the output amplifier to 0.25 Vpp. For ac levels below this, the pre-attenuator will be used (Sheet FG6) to provide up to 14 dB additional at tenuation (for levels down to 50 mVpp) .

DS335 Synthesized Function Generator

Circuitry 5-7

Power Supplies (DS335PS9)

A transformer with multiple primary taps accommodates operation fr om 100, 120, 220 and 240 Vac mains. The secondaries are f ull-wave rectified, filtered, and regulated.

Linear power supplies which float with t he ground applied t o the BNC s hields provide + -15 , + 5 and -5.2 Vdc . There are three s eparate regulators for the +5 supplies s o as to reduce noise in critical circ uits: +5_LOGIC, +5_CLOCK, and +5_ANA LOG.

There is a 9.4 Vac tap on the secondary of the tr ansformer which is rectified, filtered, and regulated on the optional communicati ons interface to prov ide a +5 Vdc which is r eferenc ed to the line cord ground. ( S ee sheet DS340PS10).

A power-up/power-down r eset circuit asserts RESET signals t o the system whenever the unit is turned on or off. Clean resets ar e important for starting the CP U and for RAM protection on power-down.

Communications Interface (DS335PS10-Optional)

The design of the communic ations int erf ace is dictat ed by the r equirement t hat it must be ground referenced, while the rest of the syst em must float with t he BNC shield. T his requires a separat e power s upply, and opt oisolators for data and clock.

To avoid using large numbers of opto-isolators, it is nec essary to transfer data and c ommands between t he CPU and the communications int erface serially.

The RS232 interfac e is handled by a 8251 UA RT, the GPIB interface uses a TMS9914A GPIB contr oller . Both of these devices hav e a bi-direc tional data bus and several int er nal r egis ters for data and control.

To write to a register in one of these dev ices, sixteen bits must be shifted serially. (E ight bits of data, and eight 'command' bit s.) This requir es sixt een OUT instruc tions, and six teen shift instr uctions. (Only the M SB of the OUT will be transf erred to the communications interface with each OUT instruction.)

Consider a write to a register in the UART to illustrate the operat ion of the communications interf ac e. First, the eight data bits will be sent , with the MSB going first. Next the command byte, 10h, will be sent (MSB first). Both bytes will be clocked serially through the to shift registers, U1000 and U1002, with the data byte ending up in U1002 and the command byt e in U1000. The command by te, 10h, indic ates that this will be a WRITE to the RS232 register 0. Finally, a single OUT instruction will assert -CMD_STB (the command strobe), generating a -CS and -W R to the UART, wr iting the data byte to register 0.

To read a register, only the command byte and com mand strobe need be sent . F or exam ple, if t he comm and byte 49h is shifted into t he command shift regist er (U1000), and the command str obe assert ed, then register 01 in the GPIB cont roller will be read int o the shift register (U1002). The content s of t he data shift register may then be clocked down to the CPU with eight IN and eight shift instructions .

DS335 Synthesized Function Generator

5-8 Circuitry

DS335 Synthesized Function Generator

DS335 Component Parts List 5-9

Power Supp ly Parts List

REF. SRS PART VALUE DESCRIPTION

C 955 5- 00201-526 2200U Capacitor, Electrolytic, 35V, 20%, Rad C 956 5- 00100-517 2.2U Capacitor, Tantalum, 35V, 20%, Rad C 957 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 958 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 959 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 960 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 961 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 962 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 1002 5- 00192-542 22U MIN Cap, Mini Electrolytic, 50V, 20% Radial C 1003 5- 00192-542 22U MIN Cap, Mini Electrolytic, 50V, 20% Radial C 1004 5- 00192-542 22U MIN Cap, Mini Electrolytic, 50V, 20% Radial C 1005 5- 00192-542 22U MIN Cap, Mini Electrolytic, 50V, 20% Radial C 1006 5- 00192-542 22U MIN Cap, Mini Electrolytic, 50V, 20% Radial C 1013 5- 00007-501 220P Capacitor, Ceramic Disc, 50V, 10%, SL D 906 3-00062-340 KBP201G/BR-81D Integrated Circuit (Thru-hole Pkg) J 1000 1-00160- 162 IEEE488/STAND. Connector, IEEE488, Standard, R/A, Femal JP1000 1-00032-130 14 PIN DIL Connector, Male OI0 3-00446-340 6N137 I ntegrated Circuit (Thru-hole Pkg) OI1 3-00446-340 6N137 I ntegrated Circuit (Thru-hole Pkg) OI2 3-00446-340 6N137 I ntegrated Circuit (Thru-hole Pkg) OI3 3-00446-340 6N137 I ntegrated Circuit (Thru-hole Pkg) OI4 3-00446-340 6N137 I ntegrated Circuit (Thru-hole Pkg) OI5 3-00446-340 6N137 I ntegrated Circuit (Thru-hole Pkg) OI6 3-00446-340 6N137 I ntegrated Circuit (Thru-hole Pkg) P 1000 1-00016-160 RS232 25 PIN D Connector, D-Sub, Right Angle PC, Fem ale R 1000 4- 00076-401 390 Resistor, Carbon Film, 1/4W, 5% R 1001 4- 00076-401 390 Resistor, Carbon Film, 1/4W, 5% R 1002 4- 00076-401 390 Resistor, Carbon Film, 1/4W, 5% R 1003 4- 00076-401 390 Resistor, Carbon Film, 1/4W, 5% R 1004 4- 00081-401 470 Resistor, Carbon Film, 1/4W, 5% R 1005 4- 00076-401 390 Resistor, Carbon Film, 1/4W, 5% R 1006 4- 00076-401 390 Resistor, Carbon Film, 1/4W, 5% R 1007 4- 00076-401 390 Resistor, Carbon Film, 1/4W, 5% R 1008 4- 00034-401 10K Resistor, Carbon Film, 1/4W, 5% R 1009 4- 00034-401 10K Resistor, Carbon Film, 1/4W, 5% R 1010 4- 00034-401 10K Resistor, Carbon Film, 1/4W, 5% R 1011 4- 00081-401 470 Resistor, Carbon Film, 1/4W, 5% R 1012 4- 00081-401 470 Resistor, Carbon Film, 1/4W, 5% R 1013 4- 00081-401 470 Resistor, Carbon Film, 1/4W, 5% R 1014 4- 00081-401 470 Resistor, Carbon Film, 1/4W, 5% R 1015 4- 00021-401 1.0K Resistor, Carbon Film, 1/4W, 5% R 1016 4- 00021-401 1.0K Resistor, Carbon Film, 1/4W, 5% U 900 3- 00112-329 7805 Voltage Reg., TO-220 (TAB) Package U 1000 3- 00303-340 74HC164 Integrated Circuit ( Thru-hole Pkg) U 1001 3- 00045-340 74HC32 Integrated Circuit (Thru-hole Pkg) U 1002 3- 00434-340 74HC299 Integrated Circuit ( Thru-hole Pkg) U 1003 3- 00039-340 74HC14 Integrated Circuit (Thru-hole Pkg) U 1004 3- 00036-340 74HC00 Integrated Circuit (Thru-hole Pkg) U 1005 3- 00645-340 NAT9914BPD Integrated Circuit (Thru-hole Pkg) U 1006 3- 00078-340 DS75160A I nt egrated Circuit (Thru-hole Pkg) U 1007 3- 00079-340 DS75161A I nt egrated Circuit (Thru-hole Pkg) U 1008 3- 00493-340 UPD71051C Integrated Circuit (Thru-hole Pkg)

DS335 Synthesized Function Generator

5-10 DS335 Component Parts List

REF. SRS PART VALUE DESCRIPTION

U 1009 3- 00217-340 MAX232 Integrated Circuit ( Thru-hole Pkg) Z 0 0-00299-000 1/8" ADHES TAPE Hardware, Misc. Z 0 1-00048-171 14 COND Cable Assembly, Ribbon

Front Panel and Main PC Board Parts List

REF. SRS PART VALUE DESCRIPTION

BT1 6-00001- 612 BR-2/3A 2PIN PC Bat t ery C 100 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 101 5- 00192-542 22U MIN Cap, Mini Electrolytic, 50V, 20% Radial C 102 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 103 5- 00040-509 1.0U Capacitor, Electrolytic, 50V, 20%, Rad C 200 5- 00027-503 .01U Capacitor, Ceramic Disc, 50V, 20%, Z5U C 301 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 303 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 304 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 305 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 306 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 400 5- 00002-501 100P Capacitor, Ceramic Disc, 50V, 10%, SL C 500 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 501 5- 00065-513 .01U Capacitor, Mylar/Poly, 50V, 5%, Rad C 502 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 503 5- 00178-501 62P Capacitor, Ceramic Disc, 50V, 10%, SL C 504 5- 00178-501 62P Capacitor, Ceramic Disc, 50V, 10%, SL C 505 5- 00273-532 100P Capacitor, Ceramic Disc, 50V, 10% NPO C 506 5- 00273-532 100P Capacitor, Ceramic Disc, 50V, 10% NPO C 509 5- 00151-501 680P Capacitor, Ceramic Disc, 50V, 10%, SL C 510 5- 00151-501 680P Capacitor, Ceramic Disc, 50V, 10%, SL C 511 5- 00270-532 51P Capacitor, Ceramic Disc, 50V, 10% NPO C 512 5- 00270-532 51P Capacitor, Ceramic Disc, 50V, 10% NPO C 513 5- 00259-501 .002U Capacitor, Ceramic Disc, 50V, 10%, SL C 514 5- 00259-501 .002U Capacitor, Ceramic Disc, 50V, 10%, SL C 515 5- 00271-532 56P Capacitor, Ceramic Disc, 50V, 10% NPO C 516 5- 00271-532 56P Capacitor, Ceramic Disc, 50V, 10% NPO C 517 5- 00269-501 300P Capacitor, Ceramic Disc, 50V, 10%, SL C 518 5- 00269-501 300P Capacitor, Ceramic Disc, 50V, 10%, SL C 519 5- 00131-501 560P Capacitor, Ceramic Disc, 50V, 10%, SL C 520 5- 00131-501 560P Capacitor, Ceramic Disc, 50V, 10%, SL C 521 5- 00272-532 39P Capacitor, Ceramic Disc, 50V, 10% NPO C 522 5- 00272-532 39P Capacitor, Ceramic Disc, 50V, 10% NPO C 523 5- 00274-532 180P Capacitor, Ceramic Disc, 50V, 10% NPO C 524 5- 00274-532 180P Capacitor, Ceramic Disc, 50V, 10% NPO C 525 5- 00264-513 .0015U Capacitor, Mylar/Poly, 50V, 5%, Rad C 526 5- 00264-513 .0015U Capacitor, Mylar/Poly, 50V, 5%, Rad C 527 5- 00133-532 150P Capacitor, Ceramic Disc, 50V, 10% NPO C 528 5- 00133-532 150P Capacitor, Ceramic Disc, 50V, 10% NPO C 529 5- 00021-501 82P Capacitor, Ceramic Disc, 50V, 10%, SL C 530 5- 00264-513 .0015U Capacitor, Mylar/Poly, 50V, 5%, Rad C 531 5- 00021-501 82P Capacitor, Ceramic Disc, 50V, 10%, SL C 532 5- 00264-513 .0015U Capacitor, Mylar/Poly, 50V, 5%, Rad C 533 5- 00275-532 120P Capacitor, Ceramic Disc, 50V, 10% NPO C 534 5- 00131-501 560P Capacitor, Ceramic Disc, 50V, 10%, SL C 535 5- 00268-532 270P Capacitor, Ceramic Disc, 50V, 10% NPO C 536 5- 00131-501 560P Capacitor, Ceramic Disc, 50V, 10%, SL

DS335 Synthesized Function Generator

DS335 Component Parts List 5-11

REF. SRS PART VALUE DESCRIPTION

C 537 5- 00268-532 270P Capacitor, Ceramic Disc, 50V, 10% NPO C 538 5- 00275-532 120P Capacitor, Ceramic Disc, 50V, 10% NPO C 539 5- 00151-501 680P Capacitor, Ceramic Disc, 50V, 10%, SL C 540 5- 00151-501 680P Capacitor, Ceramic Disc, 50V, 10%, SL C 542 5- 00257-530 20-90P Capacitor, Variable, 200V, 5m C 600 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 601 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 602 5- 00027-503 .01U Capacitor, Ceramic Disc, 50V, 20%, Z5U C 603 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 604 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 605 5- 00100-517 2.2U Capacitor, Tantalum, 35V, 20%, Rad C 606 5- 00027-503 .01U Capacitor, Ceramic Disc, 50V, 20%, Z5U C 607 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 608 5- 00022-501 .001U Capacitor, Ceramic Disc, 50V, 10%, SL C 700 5- 00002-501 100P Capacitor, Ceramic Disc, 50V, 10%, SL C 701 5- 00022-501 .001U Capacitor, Ceramic Disc, 50V, 10%, SL C 702 5- 00100-517 2.2U Capacitor, Tantalum, 35V, 20%, Rad C 703 5- 00267-526 1000U Capacitor, Electrolytic, 35V, 20%, Rad C 704 5- 00100-517 2.2U Capacitor, Tantalum, 35V, 20%, Rad C 705 5- 00267-526 1000U Capacitor, Electrolytic, 35V, 20%, Rad C 707 5- 00107-530 1.8-6P Capacitor, Variable, 200V, 5m C 708 5- 00003-501 10P Capacitor, Ceramic Disc, 50V, 10%, SL C 709 5- 00017-501 47P Capacitor, Ceramic Disc, 50V, 10%, SL C 710 5- 00017-501 47P Capacitor, Ceramic Disc, 50V, 10%, SL C 711 5- 00022-501 .001U Capacitor, Ceramic Disc, 50V, 10%, SL C 712 5- 00022-501 .001U Capacitor, Ceramic Disc, 50V, 10%, SL C 800 5- 00100-517 2.2U Capacitor, Tantalum, 35V, 20%, Rad C 801 5- 00100-517 2.2U Capacitor, Tantalum, 35V, 20%, Rad C 802 5- 00100-517 2.2U Capacitor, Tantalum, 35V, 20%, Rad C 803 5- 00100-517 2.2U Capacitor, Tantalum, 35V, 20%, Rad C 804 5- 00100-517 2.2U Capacitor, Tantalum, 35V, 20%, Rad C 805 5- 00100-517 2.2U Capacitor, Tantalum, 35V, 20%, Rad C 806 5- 00100-517 2.2U Capacitor, Tantalum, 35V, 20%, Rad C 807 5- 00100-517 2.2U Capacitor, Tantalum, 35V, 20%, Rad C 808 5- 00100-517 2.2U Capacitor, Tantalum, 35V, 20%, Rad C 809 5- 00100-517 2.2U Capacitor, Tantalum, 35V, 20%, Rad C 810 5- 00100-517 2.2U Capacitor, Tantalum, 35V, 20%, Rad C 811 5- 00100-517 2.2U Capacitor, Tantalum, 35V, 20%, Rad C 812 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 813 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 814 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 815 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 816 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 817 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 818 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 819 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 820 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 821 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 822 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 823 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 824 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 825 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 826 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 827 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX

DS335 Synthesized Function Generator

5-12 DS335 Component Parts List

REF. SRS PART VALUE DESCRIPTION

C 828 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 829 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 830 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 831 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 832 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 833 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 834 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 835 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 836 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 837 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 838 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 839 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 840 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 841 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 842 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 843 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 844 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 845 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 846 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 847 5- 00259-501 .002U Capacitor, Ceramic Disc, 50V, 10%, SL C 848 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 849 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 850 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 851 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 852 5- 00259-501 .002U Capacitor, Ceramic Disc, 50V, 10%, SL C 900 5- 00225-548 .1U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX C 944 5- 00201-526 2200U Capacitor, Electrolytic, 35V, 20%, Rad C 945 5- 00201-526 2200U Capacitor, Electrolytic, 35V, 20%, Rad C 953 5- 00196-520 6800U Capacitor, Electrolytic, 16V, 20%, Rad C 954 5- 00196-520 6800U Capacitor, Electrolytic, 16V, 20%, Rad C 963 5- 00027-503 .01U Capacitor, Ceramic Disc, 50V, 20%, Z5U CX1 5-00262-548 .01U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX CX2 5-00262-548 .01U AXIAL Capacitor, Ceramic, 50V,+80/-20% Z5U AX D 1 3-00012-306 GREEN LED, Rectangular D 2 3-00012-306 GREEN LED, Rectangular D 4 3- 00885-306 YELLOW LED, Rectangular D 5 3-00012-306 GREEN LED, Rectangular D 6 3-00012-306 GREEN LED, Rectangular D 7 3-00012-306 GREEN LED, Rectangular D 8 3-00012-306 GREEN LED, Rectangular D 9 3-00012-306 GREEN LED, Rectangular D 10 3-00012-306 GREEN LED, Rectangular D 11 3-00012-306 GREEN LED, Rectangular D 12 3-00012-306 GREEN LED, Rectangular D 13 3-00012-306 GREEN LED, Rectangular D 14 3-00012-306 GREEN LED, Rectangular D 15 3-00012-306 GREEN LED, Rectangular D 16 3-00012-306 GREEN LED, Rectangular D 17 3-00012-306 GREEN LED, Rectangular D 19 3-00012-306 GREEN LED, Rectangular D 20 3-00455-310 GREEN COATED LED, Coated Rect angular D 21 3-00455-310 GREEN COATED LED, Coated Rect angular D 22 3-00455-310 GREEN COATED LED, Coated Rect angular D 23 3-00455-310 GREEN COATED LED, Coated Rect angular

DS335 Synthesized Function Generator

DS335 Component Parts List 5-13

REF. SRS PART VALUE DESCRIPTION

D 24 3-00455-310 GREEN COATED LED, Coated Rect angular D 25 3-00455-310 GREEN COATED LED, Coated Rect angular D 26 3-00884-306 RED LED, Rectangular D 27 3-00004-301 1N4148 Diode D 28 3-00004-301 1N4148 Diode D 29 3-00004-301 1N4148 Diode D 30 3-00004-301 1N4148 Diode D 101 3- 00004-301 1N4148 Diode D 102 3- 00004-301 1N4148 Diode D 103 3- 00004-301 1N4148 Diode D 200 3- 00004-301 1N4148 Diode D 700 3- 00485-301 1N5237B Diode D 701 3- 00485-301 1N5237B Diode D 900 3-00062-340 KBP201G/BR-81D Integrated Circuit (Thru-hole Pkg) D 901 3- 00226-301 1N5822 Diode D 902 3- 00226-301 1N5822 Diode D 903 3- 00226-301 1N5822 Diode D 904 3- 00226-301 1N5822 Diode D 905 3- 00203-301 1N5711 Diode J 1 1- 00038-130 40 PIN DIL Connector, M ale J 200 1-00038-130 40 PIN DIL Connector, M ale J 400 1-00003-120 BNC Connector, BNC J 401 1-00003-120 BNC Connector, BNC J 600 1-00073-120 INSL Connector, BNC J 800 1-00073-120 INSL Connector, BNC JP100 1-00032-130 14 PIN DIL Connector, Male JP200 1-00086-130 3 PIN SI Connector, Male JP800 1-00080-130 8 PIN SI Connector, Male JP900 1-00080-130 8 PIN SI Connector, Male L 500 6-00120-630 FB64-101 Ferr ite Beads L 501 6-00120-630 FB64-101 Ferr ite Beads L 600 6-00120-630 FB64-101 Ferr ite Beads N 1 4- 00498-421 680X4 Res. Network, SIP, 1/4W,2% ( Isolated) N 2 4- 00498-421 680X4 Res. Network, SIP, 1/4W,2% ( Isolated) N 3 4- 00498-421 680X4 Res. Network, SIP, 1/4W,2% ( Isolated) N 4 4- 00498-421 680X4 Res. Network, SIP, 1/4W,2% ( Isolated) N 5 4-00774-421 39X4 Res. Network, SIP, 1/4W,2% (Isolated) N 6 4-00774-421 39X4 Res. Network, SIP, 1/4W,2% (Isolated) N 7 4-00707-425 2.2KX7 Resistor Network SI P 1/4W 2% (Common) N 200 4- 00293-421 470X4 Res. Network, SIP, 1/4W,2% ( Isolated) N 300 4- 00244-421 10KX4 Res. Network, SIP, 1/4W,2% ( Isolated) N 501 4- 00293-421 470X4 Res. Network, SIP, 1/4W,2% ( Isolated) N 502 4- 00293-421 470X4 Res. Network, SIP, 1/4W,2% ( Isolated) N 503 4- 00293-421 470X4 Res. Network, SIP, 1/4W,2% ( Isolated) N 600 4- 00775-419 220X13 Res. Network, Dip, 1/4W, 2%, Common N 701 4- 00717-421 22X4 Res. Network, SIP, 1/4W,2% (Isolated) N 702 4- 00717-421 22X4 Res. Network, SIP, 1/4W,2% (Isolated) N 703 4- 00717-421 22X4 Res. Network, SIP, 1/4W,2% (Isolated) N 704 4- 00717-421 22X4 Res. Network, SIP, 1/4W,2% (Isolated) PC1 7-00457-701 DS335 MAIN Printed Cir cuit Board PC2 7-00453-701 DS335/340 FP Printed Circuit Boar d PC3 7-00450-701 DS335/40 PS/OPT Printed Circuit Board Q 101 3-00021-325 2N3904 Transistor, TO-92 Package Q 102 3-00022-325 2N3906 Transistor, TO-92 Package

DS335 Synthesized Function Generator

5-14 DS335 Component Parts List

REF. SRS PART VALUE DESCRIPTION

Q 103 3-00026-325 2N5210 Transistor, TO-92 Package Q 104 3-00026-325 2N5210 Transistor, TO-92 Package Q 200 3-00022-325 2N3906 Transistor, TO-92 Package Q 201 3-00022-325 2N3906 Transistor, TO-92 Package Q 202 3-00022-325 2N3906 Transistor, TO-92 Package Q 203 3-00022-325 2N3906 Transistor, TO-92 Package Q 500 3-00021-325 2N3904 Transistor, TO-92 Package Q 600 3-00021-325 2N3904 Transistor, TO-92 Package Q 601 3-00022-325 2N3906 Transistor, TO-92 Package Q 602 3-00021-325 2N3904 Transistor, TO-92 Package Q 603 3-00022-325 2N3906 Transistor, TO-92 Package Q 604 3-00022-325 2N3906 Transistor, TO-92 Package Q 700 3-00024-325 2N5086 Transistor, TO-92 Package Q 701 3-00027-325 2N5770 Transistor, TO-92 Package Q 702 3-00027-325 2N5770 Transistor, TO-92 Package Q 703 3-00022-325 2N3906 Transistor, TO-92 Package Q 704 3-00028-325 2N5771 Transistor, TO-92 Package Q 705 3-00028-325 2N5771 Transistor, TO-92 Package Q 706 3-00021-325 2N3904 Transistor, TO-92 Package Q 707 3-00025-325 2N5088 Transistor, TO-92 Package Q 708 3-00028-325 2N5771 Transistor, TO-92 Package Q 709 3-00027-325 2N5770 Transistor, TO-92 Package Q 710 3-00022-325 2N3906 Transistor, TO-92 Package Q 711 3-00022-325 2N3906 Transistor, TO-92 Package Q 712 3-00022-325 2N3906 Transistor, TO-92 Package Q 713 3-00447-322 2N5943 Transistor, TO-39 Package Q 714 3-00015-322 2N5583 Transistor, TO-39 Package Q 715 3-00021-325 2N3904 Transistor, TO-92 Package Q 716 3-00021-325 2N3904 Transistor, TO-92 Package Q 717 3-00021-325 2N3904 Transistor, TO-92 Package R 101 4- 00027-401 1.5K Resistor, Carbon Film, 1/4W, 5% R 102 4- 00027-401 1.5K Resistor, Carbon Film, 1/4W, 5% R 103 4- 00081-401 470 Resistor, Carbon Film, 1/4W, 5% R 104 4- 00081-401 470 Resistor, Carbon Film, 1/4W, 5% R 105 4- 00031-401 100 Resistor, Carbon Film, 1/4W, 5% R 106 4- 00034-401 10K Resistor, Carbon Film, 1/4W, 5% R 107 4- 00032-401 100K Resistor, Carbon Film , 1/4W, 5% R 108 4- 00034-401 10K Resistor, Carbon Film, 1/4W, 5% R 109 4- 00021-401 1.0K Resistor, Carbon Film, 1/4W, 5% R 110 4- 00032-401 100K Resistor, Carbon Film , 1/4W, 5% R 229 4- 00022-401 1.0M Resistor, Carbon Film, 1/4W, 5% R 300 4- 00218-408 10.00K Resistor, Metal Film, 1/8W, 0. 1%, 25ppm R 302 4- 00034-401 10K Resistor, Carbon Film, 1/4W, 5% R 303 4- 00185-407 4.02K Resistor, Metal Film, 1/8W, 1%, 50PPM R 304 4- 00130-407 1.00K Resistor, Metal Film, 1/8W, 1%, 50PPM R 305 4- 00218-408 10.00K Resistor, Metal Film, 1/8W, 0. 1%, 25ppm R 316 4- 00138-407 10.0K Resistor, Metal Film, 1/8W, 1%, 50PPM R 318 4- 00210-407 9.09K Resistor, Metal Film, 1/8W, 1%, 50PPM R 400 4- 00309-407 3.32K Resistor, Metal Film, 1/8W, 1%, 50PPM R 401 4- 00130-407 1.00K Resistor, Metal Film, 1/8W, 1%, 50PPM R 402 4- 00138-407 10.0K Resistor, Metal Film, 1/8W, 1%, 50PPM R 403 4- 00165-407 200 Resistor, Metal Film , 1/8W, 1%, 50PPM R 406 4- 00034-401 10K Resistor, Carbon Film, 1/4W, 5% R 407 4- 00021-401 1.0K Resistor, Carbon Film, 1/4W, 5%

DS335 Synthesized Function Generator

DS335 Component Parts List 5-15

REF. SRS PART VALUE DESCRIPTION

R 500 4- 00138-407 10.0K Resistor, Metal Film, 1/8W, 1%, 50PPM R 501 4- 00141-407 100 Resistor, Metal Film , 1/8W, 1%, 50PPM R 502 4- 00141-407 100 Resistor, Metal Film , 1/8W, 1%, 50PPM R 503 4- 00141-407 100 Resistor, Metal Film , 1/8W, 1%, 50PPM R 504 4- 00141-407 100 Resistor, Metal Film , 1/8W, 1%, 50PPM R 505 4- 00506-407 35.7K Resistor, Metal Film, 1/8W, 1%, 50PPM R 506 4- 00702-407 1.78K Resistor, Metal Film, 1/8W, 1%, 50PPM R 507 4- 00702-407 1.78K Resistor, Metal Film, 1/8W, 1%, 50PPM R 508 4- 00776-407 178 Resistor, Metal Film , 1/8W, 1%, 50PPM R 509 4- 00776-407 178 Resistor, Metal Film , 1/8W, 1%, 50PPM R 510 4- 00724-407 226 Resistor, Metal Film , 1/8W, 1%, 50PPM R 511 4- 00719-401 4.7 Resistor, Carbon Film, 1/4W, 5% R 512 4- 00719-401 4.7 Resistor, Carbon Film, 1/4W, 5% R 513 4- 00724-407 226 Resistor, Metal Film , 1/8W, 1%, 50PPM R 601 4- 00473-407 11.0K Resistor, Metal Film, 1/8W, 1%, 50PPM R 602 4- 00473-407 11.0K Resistor, Metal Film, 1/8W, 1%, 50PPM R 603 4- 00166-407 200K Resistor, Metal Film, 1/8W, 1%, 50PPM R 604 4- 00142-407 100K Resistor, Metal Film, 1/8W, 1%, 50PPM R 605 4- 00021-401 1.0K Resistor, Carbon Film, 1/4W, 5% R 606 4- 00191-407 49.9 Resistor, Metal Film, 1/8W, 1%, 50PPM R 607 4- 00031-401 100 Resistor, Carbon Film, 1/4W, 5% R 608 4- 00031-401 100 Resistor, Carbon Film, 1/4W, 5% R 609 4- 00031-401 100 Resistor, Carbon Film, 1/4W, 5% R 610 4- 00031-401 100 Resistor, Carbon Film, 1/4W, 5% R 611 4- 00130-407 1.00K Resistor, Metal Film, 1/8W, 1%, 50PPM R 612 4- 00141-407 100 Resistor, Metal Film , 1/8W, 1%, 50PPM R 613 4- 00141-407 100 Resistor, Metal Film , 1/8W, 1%, 50PPM R 614 4- 00132-407 1.10K Resistor, Metal Film, 1/8W, 1%, 50PPM R 615 4- 00215-407 909 Resistor, Metal Film , 1/8W, 1%, 50PPM R 616 4- 00030-401 10 Resistor, Carbon Film, 1/4W, 5% R 617 4- 00056-401 22 Resistor, Carbon Film, 1/4W, 5% R 618 4- 00302-407 82.5 Resistor, Metal Film, 1/8W, 1%, 50PPM R 619 4- 00685-408 100 Resistor, Metal Film , 1/8W, 0.1%, 25ppm R 620 4- 00031-401 100 Resistor, Carbon Film, 1/4W, 5% R 621 4- 00132-407 1.10K Resistor, Metal Film, 1/8W, 1%, 50PPM R 622 4- 00215-407 909 Resistor, Metal Film , 1/8W, 1%, 50PPM R 623 4- 00030-401 10 Resistor, Carbon Film, 1/4W, 5% R 624 4- 00081-401 470 Resistor, Carbon Film, 1/4W, 5% R 625 4- 00081-401 470 Resistor, Carbon Film, 1/4W, 5% R 626 4- 00112-402 47 Resistor, Carbon Comp, 1/2W, 5% R 627 4- 00477-407 432 Resistor, Metal Film , 1/8W, 1%, 50PPM R 628 4- 00777-407 11.5 Resistor, Metal Film, 1/8W, 1%, 50PPM R 635 4- 00778-407 44.2 Resistor, Metal Film, 1/8W, 1%, 50PPM R 636 4- 00777-407 11.5 Resistor, Metal Film, 1/8W, 1%, 50PPM R 637 4- 00777-407 11.5 Resistor, Metal Film, 1/8W, 1%, 50PPM R 638 4- 00777-407 11.5 Resistor, Metal Film, 1/8W, 1%, 50PPM R 639 4- 00777-407 11.5 Resistor, Metal Film, 1/8W, 1%, 50PPM R 640 4- 00777-407 11.5 Resistor, Metal Film, 1/8W, 1%, 50PPM R 641 4- 00777-407 11.5 Resistor, Metal Film, 1/8W, 1%, 50PPM R 648 4- 00778-407 44.2 Resistor, Metal Film, 1/8W, 1%, 50PPM R 649 4- 00777-407 11.5 Resistor, Metal Film, 1/8W, 1%, 50PPM R 650 4- 00777-407 11.5 Resistor, Metal Film, 1/8W, 1%, 50PPM R 651 4- 00777-407 11.5 Resistor, Metal Film, 1/8W, 1%, 50PPM R 652 4- 00777-407 11.5 Resistor, Metal Film, 1/8W, 1%, 50PPM

DS335 Synthesized Function Generator

5-16 DS335 Component Parts List

REF. SRS PART VALUE DESCRIPTION

R 653 4- 00777-407 11.5 Resistor, Metal Film, 1/8W, 1%, 50PPM R 654 4- 00777-407 11.5 Resistor, Metal Film, 1/8W, 1%, 50PPM R 655 4- 00777-407 11.5 Resistor, Metal Film, 1/8W, 1%, 50PPM R 656 4- 00031-401 100 Resistor, Carbon Film, 1/4W, 5% R 657 4- 00031-401 100 Resistor, Carbon Film, 1/4W, 5% R 660 4- 00130-407 1.00K Resistor, Metal Film, 1/8W, 1%, 50PPM R 661 4- 00193-407 499 Resistor, Metal Film , 1/8W, 1%, 50PPM R 662 4- 00193-407 499 Resistor, Metal Film , 1/8W, 1%, 50PPM R 663 4- 00193-407 499 Resistor, Metal Film , 1/8W, 1%, 50PPM R 664 4- 00193-407 499 Resistor, Metal Film , 1/8W, 1%, 50PPM R 665 4- 00158-407 2.00K Resistor, Metal Film, 1/8W, 1%, 50PPM R 666 4- 00158-407 2.00K Resistor, Metal Film, 1/8W, 1%, 50PPM R 667 4- 00166-407 200K Resistor, Metal Film, 1/8W, 1%, 50PPM R 668 4- 00165-407 200 Resistor, Metal Film , 1/8W, 1%, 50PPM R 669 4- 00441-401 9.1 Resistor, Carbon Film, 1/4W, 5% R 670 4- 00472-407 806 Resistor, Metal Film , 1/8W, 1%, 50PPM R 700 4- 00138-407 10.0K Resistor, Metal Film, 1/8W, 1%, 50PPM R 701 4- 00138-407 10.0K Resistor, Metal Film, 1/8W, 1%, 50PPM R 702 4- 00142-407 100K Resistor, Metal Film, 1/8W, 1%, 50PPM R 703 4-00353-441 100 Pot, Multi-Turn Trim, 3/8" Squar e Top Ad R 704 4- 00158-407 2.00K Resistor, Metal Film, 1/8W, 1%, 50PPM R 705 4- 00716-407 1.40K Resistor, Metal Film, 1/8W, 1%, 50PPM R 706 4- 00158-407 2.00K Resistor, Metal Film, 1/8W, 1%, 50PPM R 707 4- 00716-407 1.40K Resistor, Metal Film, 1/8W, 1%, 50PPM R 708 4- 00779-407 133 Resistor, Metal Film , 1/8W, 1%, 50PPM R 709 4- 00779-407 133 Resistor, Metal Film , 1/8W, 1%, 50PPM R 711 4- 00771-407 66.5 Resistor, Metal Film, 1/8W, 1%, 50PPM R 713 4- 00771-407 66.5 Resistor, Metal Film, 1/8W, 1%, 50PPM R 714 4- 00165-407 200 Resistor, Metal Film , 1/8W, 1%, 50PPM R 716 4- 00512-407 80.6 Resistor, Metal Film, 1/8W, 1%, 50PPM R 717 4- 00048-401 2.2K Resistor, Carbon Film, 1/4W, 5% R 718 4- 00048-401 2.2K Resistor, Carbon Film, 1/4W, 5% R 720 4- 00165-407 200 Resistor, Metal Film , 1/8W, 1%, 50PPM R 721 4- 00512-407 80.6 Resistor, Metal Film, 1/8W, 1%, 50PPM R 722 4- 00165-407 200 Resistor, Metal Film , 1/8W, 1%, 50PPM R 723 4- 00142-407 100K Resistor, Metal Film, 1/8W, 1%, 50PPM R 727 4- 00714-401 2.7 Resistor, Carbon Film, 1/4W, 5% R 728 4- 00714-401 2.7 Resistor, Carbon Film, 1/4W, 5% R 729 4- 00525-407 7.5 Resistor, Metal Film, 1/8W, 1%, 50PPM R 730 4- 00714-401 2.7 Resistor, Carbon Film, 1/4W, 5% R 731 4- 00786-439 49.9 Resistor, Metal Film, 1/4W, 1%, 50ppm R 733 4- 00714-401 2.7 Resistor, Carbon Film, 1/4W, 5% R 736 4- 00141-407 100 Resistor, Metal Film , 1/8W, 1%, 50PPM R 737 4- 00141-407 100 Resistor, Metal Film , 1/8W, 1%, 50PPM R 740 4- 00322-407 316 Resistor, Metal Film , 1/8W, 1%, 50PPM R 741 4- 00141-407 100 Resistor, Metal Film , 1/8W, 1%, 50PPM R 742 4- 00141-407 100 Resistor, Metal Film , 1/8W, 1%, 50PPM R 744 4- 00165-407 200 Resistor, Metal Film , 1/8W, 1%, 50PPM R 745 4- 00525-407 7.5 Resistor, Metal Film, 1/8W, 1%, 50PPM R 746 4- 00322-407 316 Resistor, Metal Film , 1/8W, 1%, 50PPM R 747 4- 00780-407 255 Resistor, Metal Film , 1/8W, 1%, 50PPM R 748 4- 00055-401 20K Resistor, Carbon Film, 1/4W, 5% R 749 4- 00056-401 22 Resistor, Carbon Film, 1/4W, 5% R 750 4- 00056-401 22 Resistor, Carbon Film, 1/4W, 5%

DS335 Synthesized Function Generator

DS335 Component Parts List 5-17

REF. SRS PART VALUE DESCRIPTION

R 751 4- 00056-401 22 Resistor, Carbon Film, 1/4W, 5% R 752 4- 00056-401 22 Resistor, Carbon Film, 1/4W, 5% R 800 4- 00749-439 432 Resistor, Metal Film , 1/4W, 1%, 50ppm R 801 4- 00749-439 432 Resistor, Metal Film , 1/4W, 1%, 50ppm R 802 4- 00777-407 11.5 Resistor, Metal Film, 1/8W, 1%, 50PPM R 803 4- 00750-439 221 Resistor, Metal Film , 1/4W, 1%, 50ppm R 804 4- 00750-439 221 Resistor, Metal Film , 1/4W, 1%, 50ppm R 805 4- 00751-439 23.7 Resistor, Metal Film, 1/4W, 1%, 50ppm R 806 4- 00752-439 232 Resistor, Metal Film , 1/4W, 1%, 50ppm R 807 4- 00752-439 232 Resistor, Metal Film , 1/4W, 1%, 50ppm R 808 4- 00752-439 232 Resistor, Metal Film , 1/4W, 1%, 50ppm R 809 4- 00752-439 232 Resistor, Metal Film , 1/4W, 1%, 50ppm R 810 4- 00753-439 52.3 Resistor, Metal Film, 1/4W, 1%, 50ppm R 8111 4- 00754-439 154 Resistor, Metal Film , 1/4W, 1%, 50ppm R 812 4- 00755-439 137 Resistor, Metal Film , 1/4W, 1%, 50ppm R 813 4- 00755-439 137 Resistor, Metal Film , 1/4W, 1%, 50ppm R 814 4- 00755-439 137 Resistor, Metal Film , 1/4W, 1%, 50ppm R 815 4- 00755-439 137 Resistor, Metal Film , 1/4W, 1%, 50ppm R 817 4- 00272-407 221 Resistor, Metal Film , 1/8W, 1%, 50PPM R 818 4- 00202-407 698 Resistor, Metal Film , 1/8W, 1%, 50PPM R 900 4- 00022-401 1.0M Resistor, Carbon Film, 1/4W, 5% R 901 4- 00034-401 10K Resistor, Carbon Film, 1/4W, 5% R 902 4- 00032-401 100K Resistor, Carbon Film , 1/4W, 5% SO104 1-00026-150 28 PIN 600 MIL Socket, THRU-HOLE SO408 1-00108-150 PLCC 68 TH Socket, THRU-HOLE SP100 6-00096- 600 MINI Misc. Components SW1 7-00448-740 DS335/340 Keypad, Conductive Rubber SW900 2-00023-218 DPDT Switch, Panel Mount, Power, Rocker T 500 6-00138-601 T37- 15-8 Inductor T 501 6-00139-601 T37- 15-12 Inductor T 502 6-00141-601 T37- 15-14 Inductor T 503 6-00140-601 T37- 15-13 Inductor T 504 6-00139-601 T37- 15-12 Inductor T 505 6-00141-601 T37- 15-14 Inductor T 600 6-00157-601 DS335 I nductor T 800 6-00157-601 DS335 I nductor T 801 6-00157-601 DS335 I nductor T 900 1-00036-116 7 PI N, WHITE Header, Amp, MTA-156 TP100 1-00143-101 TEST JACK Vertical Test Jack TP101 1-00143-101 TEST JACK Vertical Test Jack TP102 1-00143-101 TEST JACK Vertical Test Jack TP103 1-00143-101 TEST JACK Vertical Test Jack TP500 1-00143-101 TEST JACK Vertical Test Jack U 1 3- 00288-340 HDSP-H101 I nt egrated Circuit (Thru-hole Pkg) U 2 3- 00288-340 HDSP-H101 I nt egrated Circuit (Thru-hole Pkg) U 3 3- 00288-340 HDSP-H101 I nt egrated Circuit (Thru-hole Pkg) U 4 3- 00288-340 HDSP-H101 I nt egrated Circuit (Thru-hole Pkg) U 5 3- 00288-340 HDSP-H101 I nt egrated Circuit (Thru-hole Pkg) U 6 3- 00288-340 HDSP-H101 I nt egrated Circuit (Thru-hole Pkg) U 7 3- 00288-340 HDSP-H101 I nt egrated Circuit (Thru-hole Pkg) U 8 3- 00288-340 HDSP-H101 I nt egrated Circuit (Thru-hole Pkg) U 100 3- 00298-340 Z80H Integrated Circuit (Thru-hole Pkg) U 101 3- 00049-340 74HC74 Integrated Circuit (Thru-hole Pkg) U 102 3- 00155-340 74HC04 Integrated Circuit (Thru-hole Pkg)

DS335 Synthesized Function Generator

5-18 DS335 Component Parts List

REF. SRS PART VALUE DESCRIPTION

U 103 3- 00045-340 74HC32 Integrated Circuit (Thru-hole Pkg) U 106 3- 00491-340 UPD71054C Integrated Circuit (Thru-hole Pkg) U 107 3- 00049-340 74HC74 Integrated Circuit (Thru-hole Pkg) U 108 3- 00158-340 74HC154N Integrated Cir cuit (Thru-hole Pkg) U 109 3- 00411-340 74HC273 Integrated Circuit ( Thru-hole Pkg) U 110 3- 00044-340 74HC244 Integrated Circuit ( Thru-hole Pkg) U 111 3- 00039-340 74HC14 Integrated Circuit (Thru-hole Pkg) U 200 3- 00046-340 74HC374 Integrated Circuit ( Thru-hole Pkg) U 201 3- 00046-340 74HC374 Integrated Circuit ( Thru-hole Pkg) U 202 3- 00046-340 74HC374 Integrated Circuit ( Thru-hole Pkg) U 203 3- 00046-340 74HC374 Integrated Circuit ( Thru-hole Pkg) U 204 3- 00044-340 74HC244 Integrated Circuit ( Thru-hole Pkg) U 206 3-00366-341 32KX8-35 STATIC RAM, I.C. U 300 3- 00319-340 AD586JN Integrated Circuit (Thru-hole Pkg) U 301 3- 00088-340 LF353 Int egrated Circuit (Thru-hole Pkg) U 302 3- 00105-340 LM741 Integrated Circuit (Thru-hole Pkg) U 303 3- 00415-340 AD7845 Int egrated Circuit (Thru-hole Pkg) U 304 3- 00270-340 74HC4051 Integrated Circuit (Thru-hole Pkg) U 305 3- 00411-340 74HC273 Integrated Circuit ( Thru-hole Pkg) U 306 3- 00087-340 LF347 Int egrated Circuit (Thru-hole Pkg) U 400 3-00366-341 32KX8-35 STATIC RAM, I.C. U 401 3- 00088-340 LF353 Int egrated Circuit (Thru-hole Pkg) U 402 3- 00058-340 AD7524 Int egrated Circuit (Thru-hole Pkg) U 404 3- 00411-340 74HC273 Integrated Circuit ( Thru-hole Pkg) U 405 3- 00165-340 74HC08 Integrated Circuit (Thru-hole Pkg) U 406 3- 00045-340 74HC32 Integrated Circuit (Thru-hole Pkg) U 407 3- 00261-340 74LS245 I nt egrated Circuit (Thru-hole Pkg) U 408 3- 00421-340 F107563FN Integrated Circuit ( Thru-hole Pkg) U 409 3- 00528-342 U409/27C256 PRO EPROM/PROM, I.C. U 410 3- 00486-340 74F273 Int egrated Circuit (Thru-hole Pkg) U 411 3- 00529-342 U411/27C256 PRO EPROM/PROM, I.C. U 412 3- 00486-340 74F273 Int egrated Circuit (Thru-hole Pkg) U 413 3- 00411-340 74HC273 Integrated Circuit ( Thru-hole Pkg) U 500 3- 00482-340 TDC1012N7C2 Integrated Circuit (Thru-hole Pkg) U 501 3- 00196-335 HS-212S-5 Relay U 502 3- 00196-335 HS-212S-5 Relay U 503 3- 00105-340 LM741 Integrated Circuit (Thru-hole Pkg) U 504 3- 00190-340 10MHZ 25PPM Integrated Circuit (Thru-hole Pkg) U 600 3- 00270-340 74HC4051 Integrated Circuit (Thru-hole Pkg) U 601 3- 00437-340 AD9696KN I ntegrated Circuit (Thru-hole Pkg) U 602 3- 00044-340 74HC244 Integrated Circuit ( Thru-hole Pkg) U 603 3- 00196-335 HS-212S-5 Relay U 604 3- 00270-340 74HC4051 Integrated Circuit (Thru-hole Pkg) U 605 3- 00066-340 CA3140E Integrated Circuit (Thru-hole Pkg) U 700 3- 00066-340 CA3140E Integrated Circuit (Thru-hole Pkg) U 701 3- 00487-340 LM1458 Int egrated Circuit (Thru-hole Pkg) U 800 3- 00411-340 74HC273 Integrated Circuit ( Thru-hole Pkg) U 801 3- 00195-340 CA3082 Int egrated Circuit (Thru-hole Pkg) U 802 3- 00196-335 HS-212S-5 Relay U 803 3- 00196-335 HS-212S-5 Relay U 804 3- 00196-335 HS-212S-5 Relay U 805 3- 00196-335 HS-212S-5 Relay U 807 3- 00114-329 7815 Voltage Reg., TO-220 (TAB) Package U 808 3- 00120-329 7915 Voltage Reg., TO-220 (TAB) Package

DS335 Synthesized Function Generator

DS335 Component Parts List 5-19

REF. SRS PART VALUE DESCRIPTION

U 809 3- 00141-329 LM337T Voltage Reg., TO- 220 (TAB) Package U 810 3- 00112-329 7805 Voltage Reg., TO-220 (TAB) Package U 811 3- 00112-329 7805 Voltage Reg., TO-220 (TAB) Package U 812 3- 00112-329 7805 Voltage Reg., TO-220 (TAB) Package VR900 4-00723-435 82V/2500A Var ist or, Zinc Oxide Nonlinear Resistor Z 0 0-00014-002 6J4 Power_Entry Hardware Z 0 0-00025-005 3/8" Lugs Z 0 0-00043-011 4-40 KEP Nut, Kep Z 0 0-00050-011 8-32 KEP Nut, Kep Z 0 0-00051-056 RG174 Cable, Coax & Misc. Z 0 0-00079-031 4-40X3/16 M/F St andoff Z 0 0-00089-033 4" Tie Z 0 0-00111-053 1-3/4"#24B Wire #24 UL1007 Strip 1/4x1/4 Tin Z 0 0-00112-053 1-3/4"#24R Wire #24 UL1007 Strip 1/4x1/4 Tin Z 0 0-00150-026 4-40X1/4PF Screw, Black, All Types Z 0 0-00163-007 TO-5 Heat Sinks Z 0 0-00181-020 6-32X1/4PF Scr ew, Flathead Phillips Z 0 0-00187-021 4-40X1/4PP Screw, Panhead Phillips Z 0 0-00207-003 TO-5 I nsulators Z 0 0-00208-020 4-40X3/8PF Scr ew, Flathead Phillips Z 0 0-00231-043 #4 SHOULDER Washer, nylon Z 0 0-00237-016 F1404 Power Button Z 0 0-00243-003 TO-220 Insulators Z 0 0-00259-021 4-40X1/2"PP Screw, Panhead Phillips Z 0 0-00267-052 6-1/2" #22 RED Wire #22 UL1007 Z 0 0-00268-052 6-1/2" #22 BL Wire #22 UL1007 Z 0 0-00304-043 7/8X3/8X1/16 Washer, nylon Z 0 0-00386-003 BNC BUSHING Insulators Z 0 0-00407-032 SOLDR SLV RG174 Termination Z 0 0-00500-000 554808-1 Hardware, Misc. Z 0 1-00034-113 7 PIN, 18AWG/OR Connector, Amp, MTA- 156 Z 0 1-00072-112 8 PIN, 28AWG/GR Connector, Amp, MTA- 100 Z 0 1-00087-131 2 PIN JUMPER Connector, Female Z 0 1-00134-171 40 COND Cable Assembly, Ribbon Z 0 1-00172-170 9535 Cable Assembly, Multiconduct or Z 0 4-00541-435 130V/1200A Varist or, Zinc Oxide Nonlinear Resistor Z 0 6-00003-611 .5A 3AG Fuse Z 0 6-00128-610 DS335/340 Tr ansformer Z 0 6-00131-623 10MHZ Temp. Controlled Crystal Os c. Z 0 6-00212-630 1"X.25"CYL Ferrite Beads Z 0 7-00217-735 PS300-40 Injection M olded Plastic Z 0 7-00447-709 DS335-1 Lexan Overlay Z 0 7-00449-709 DS335 Lexan Overlay Z 0 7-00451-720 DS335-4 & -5 Fabricated Part Z 0 7-00452-720 DS335-6C Fabr icated Part Z 0 9-00458-917 DS335/340/345 Product Labels Z 0 9-00552-924 COPPERFOIL;1" Tape, All types

Miscellaneous and chassis Assembly Parts List

REF. SRS PART VALUE DESCRIPTION

U 104 3- 00449-342 27C256-120 EPROM/PROM, I.C. Z 0 0-00179-000 RIGHT FOOT Hardware, Misc. Z 0 0-00180-000 LEFT FOOT Hardware, Misc.

DS335 Synthesized Function Generator

5-20 DS335 Component Parts List

REF. SRS PART VALUE DESCRIPTION

Z 0 0-00204-000 REAR FOOT Hardware, Misc . Z 0 0-00248-026 10-32X3/8TRUSSP Screw, Black, All Types Z 0 0-00315-021 6-32X7/16 PP Screw, Panhead Phillips Z 0 0-00326-026 8-32X1/4PP Screw, Black, All Types Z 0 0-00396-000 BE CU / DDS Hardware, Misc. Z 0 0-00590-066 0097-0555-02 Copper Foil Tape, Self Adhesive Z 0 7-00122-720 DG535-36 Fabricated Part Z 0 7-00259-720 SR560-28 Fabricated Part Z 0 7-00260-720 SR560-27 Fabricated Part

DS335 Synthesized Function Generator

Stanford Research Systems DS335 Service manual

Specifications and Main Features

Frequently Asked Questions

User Manual