GW Instek SFG-2000 User Manual

Synthesized Function Generator

SFG-2000/SFG-2100 Series

USER MANUAL

GW INSTEK PART NO. 82FG-21200MD

This manual contains proprietary information, which is protected by copyrights. All rights are reserved. No part of this manual may be photocopied, reproduced or translated to another language without prior written consent of Good Will company.

The information in this manual was correct at the time of printing. However, Good Will continues to improve products and reserves the rights to change specification, equipment, and maintenance procedures at any time without notice.

ISO-9001 CERTIFIED MANUFACTURER

Good Will Instrument Co., Ltd.

No. 7-1, Jhongsing Rd., Tucheng City, Taipei County 236, Taiwan.

Table of Contents

SAFETY INSTRUCTIONS ................................................... 5

SFG-2000 Series User Manual

FREQUENCY MODULATION........................................... 38

COUNTER INPUT............................................................ 40

Safety Symbols......................................................... 5

Safety Guidelines ..................................................... 6

GETTING STARTED........................................................... 9

Technical background .............................................10

Lineup/Features......................................................12

Front Panel .............................................................13

Rear Panel...............................................................19

Set Up.....................................................................20

Operation Shortcuts ...............................................22

Default Setting Contents.........................................24

SINE/SQUARE/TRIANGLE WAVE.....................................25

Select the waveform................................................26

Set the Frequency....................................................26

Set the Duty Cycle (Square Waveform) ...................28

Set Amplitude .........................................................29

Set Offset................................................................30

TTL CMOS OUTPUT.........................................................31

Select the waveform................................................32

Set the Frequency....................................................32

Set the Duty Cycle...................................................33

Set Amplitude .........................................................34

STORE/RECALL SETTING................................................ 42

APPLICATION EXAMPLES ............................................... 44

Reference Signal for PLL System ............................ 44

Trouble-Shooting Signal Source..............................44

Transistor DC Bias Characteristics Test.................. 45

Amplifier Over-Load Characteristic Test.................46

Amplifier Transient Characteristics Test .................46

Logic Circuit Test.................................................... 48

Impedance Matching Network Test ........................ 48

Speaker Driver Test.................................................49

Sweep for Speaker Test...........................................50

FAQ ................................................................................. 51

APPENDIX ....................................................................... 52

Error Messages ......................................................52

Specification...........................................................53

Declaration of Conformity ...................................... 55

INDEX ............................................................................. 56

SWEEP..............................................................................35

AMPLITUDE MODULATION ............................................37

SAFETY INSTRUCTIONS

This chapter contains important safety instructions that you must follow when operating SFG-2000 series and when keeping it in storage. Read the following before any operation to insure your safety and to keep the best condition for SFG-2000 series.

Safety Symbols

These safety symbols may appear in this manual or on SFG-2000 series.

Warning: Identifies conditions or practices that could

WARNING

CAUTION

result in injury or loss of life.

Caution: Identifies conditions or practices that could result in damage to SFG-2000 series or to other properties.

Attention Refer to the Manual

Earth (ground) Terminal

SFG-2000 Series User Manual

Safety Guidelines

General Guideline

CAUTION

• Do not place any heavy object on SFG-2000 series.

• Avoid severe impacts or rough handling that leads to

damaging SFG-2000 series.

• Do not discharge static electricity to SFG-2000 series.

• Use only mating connectors, not bare wires, for the

terminals.

• Do not block or obstruct cooling vent opening.

• Do not perform measurements at power source and

building installation site (Note below).

• Do not disassemble SFG-2000 series unless you are

qualified as service personnel.

(Note) EN 61010-1:2001 specifies the measurement categories and their requirements as follows. SFG-2000 series falls under category II.

Power Supply

WARNING

• Measurement category IV is for measurement performed at the

source of low-voltage installation.

• Measurement category III is for measurement performed in the

building installation.

• Measurement category II is for measurement performed on the

circuits directly connected to the low voltage installation.

• Input voltage: 115/230V AC +10%, −15%, 50/60Hz

• The power supply voltage should not fluctuate more

than 10%.

• Connect the protective grounding conductor of the

power cord to earth ground, to avoid electrical shock.

Fuse

WARNING

• Fuse type: T0.125A/ 250V

• Only service personnel are allowed to access internal

fuse holders.

• Replace the fuse with the specified type and rating

only, for continued fire protection.

• Disconnect the power cord before fuse replacement.

• Make sure the cause of the fuse blowout is fixed

before fuse replacement.

SAFETY INSTRUCTIONS

SFG-2000 Series User Manual

Cleaning SFG-2000 series

Operation Environment

Storage Environment

• Disconnect the power cord before cleaning.

• Use a soft cloth dampened in a solution of mild

detergent and water. Do not spray any liquid into SFG-2000 series.

• Do not use chemicals or cleaners containing harsh

materials such as benzene, toluene, xylene, and acetone.

• Location: Indoor, no direct sunlight, dust free, almost

non-conductive pollution (Note below)

• Relative Humidity: < 80%

• Altitude: < 2000m

• Temperature: 0°C to 40°C

(Note) EN 61010-1:2001 specifies the pollution degrees and their requirements as follows. SFG-2000 series falls under degree 2. Pollution refers to “addition of foreign matter, solid, liquid, or gaseous (ionized gases), that may produce a reduction of dielectric strength or surface resistivity”.

• Pollution degree 1: No pollution or only dry, non-conductive

pollution occurs. The pollution has no influence.

• Pollution degree 2: Normally only non-conductive pollution

occurs. Occasionally, however, a temporary conductivity caused by condensation must be expected.

• Pollution degree 3: Conductive pollution occurs, or dry,

non-conductive pollution occurs which becomes conductive due to condensation which is expected. In such conditions, equipment is normally protected against exposure to direct sunlight, precipitation, and full wind pressure, but neither temperature nor humidity is controlled.

• Location: Indoor

• Relative Humidity: < 80%

• Temperature: −10°C to 70°C

Power cord for the United Kingdom

When using SFG-2000 series in the United Kingdom, make sure the power cord meets the following safety instructions.

NOTE: This lead / appliance must only be wired by competent persons

WARNING: THIS APPLIANCE MUST BE EARTHED IMPORTANT: The wires in this lead are coloured in accordance with the following code: Green/ Yellow: Earth Blue: Neutral Brown: Live (Phase) As the colours of the wires in main leads may not correspond with the colours marking identified in your plug/appliance, proceed as follows: The wire which is coloured Green & Yellow must be connected to the Earth terminal marked with the letter E or by the earth symbol The wire which is coloured Blue must be connected to the terminal which is marked with the letter N or coloured Blue or Black. The wire which is coloured Brown must be connected to the terminal marked with the letter L or P or coloured Brown or Red. If in doubt, consult the instructions provided with the equipment or contact the supplier. This cable/appliance should be protected by a suitably rated and approved HBC mains fuse: refer to the rating information on the equipment and/or user instructions for details. As a guide, cable of 0.75mm2 should be protected by a 3A or 5A fuse. Larger conductors would normally require 13A types, depending on the connection method used. Any moulded mains connector that requires removal /replacement must be destroyed by removal of any fuse & fuse carrier and disposed of immediately, as a plug with bared wires is hazardous if a engaged in live socket. Any re-wiring must be carried out in accordance with the information detailed on this label.

or coloured Green or Green & Yellow.

GETTING STARTED

This chapter describes SFG-2000 series in a nutshell, including main features and front/rear/display introduction. Follow the Set Up section to properly install and power up SFG-2000 series.

SFG-2000 series overview

Panel introduction

Technical background ............................................ 10

Series lineup ..........................................................12

Main features......................................................... 12

Front Panel ............................................................ 13

Rear Panel.............................................................. 19

SFG-2000 Series User Manual

Technical background

Traditional function generators

DDS methodology

SFG-2000 series uses the latest Direct Digital Synthesis (DDS) technology to generate stable, high resolution output frequency. The DDS technology solves several problems encountered in traditional function generators, as follows.

Constant current circuit methodology

This analog function generating method uses a constant current source circuit built with discrete components such as capacitors and resistors. Temperature change inside the generator greatly affects the components characteristics which lead to output frequency change. The results are poor accuracy and stability.

In DDS, the waveform data is contained in and generated from a memory. A clock controls the counter which points to the data address. The memory output is converted into analog signal by a digital to analog converter (DAC) followed by a low pass filter. The resolution is expressed as fs/2k where fs is the frequency and k is the control word, which contains more than 28bits. Because the frequency generation is referred to clock signal, this achieves much higher frequency stability and resolution than the traditional function generators.

Setup

Quick reference

Tilt stand ............................................................... 20

Power up................................................................ 21

Recall the default setting .......................................21

Functionality check ................................................ 21

Operation Shortcuts .............................................. 22

Default Setting Contents........................................ 24

GETTING STARTED

SFG-2000 Series User Manual

Block diagram

DDS synthesizer consists of Phase accumulator (counter), lookout table data (ROM), Digital-to-analog converter (DAC), and Low-pass filter (LPF).

Frequency

Control Word (K)

System Clock

(fs)

28bit

Phase

Accumulator

Table

ROM/RAM

Digital-Analog

Converter

Low-Pass

Filter

Output (fo)

28bit

12bit

The phase accumulator adds the frequency control word K at every clock cycle fs. The accumulator output points to a location in the Table ROM/RAM. The DAC converts the digital data into an analog waveform. The LPF filters out the clock frequency to provide a pure waveform.

Lineup/Features

Series lineup

Features

Lineup

SFG-2004 (4MHz) SFG-2007 (7MHz) SFG-2010 (10MHz) SFG-2020 (20MHz) SFG-2104 (4MHz) SFG-2107 (7MHz) SFG-2110 (10MHz) SFG-2120 (20MHz)

Main features

Performance

Features

Input/Output Terminals

Duty cycle

Offset TTL/

CMOS

● ● ●

Sweep AM/

Counter

― ― ― ― ― ― ― ― ― ― ― ―

● ● ● ● ● ●

• High resolution using DDS and FPGA technology

• High frequency accuracy: 20ppm

• Low distortion: −55dBc

• High resolution 100mHz maintained at full range

• Wide output frequency range: 4, 7, 10, 20MHz

• Various output waveforms: Sine, Square, and Triangle

• TTL/CMOS output

• Variable DC offset control

• Output overload protection

• Store/recall: 10 settings

• Counter up to 150MHz high frequency (SFG-2100

series)

• AM/FM with internal and external (SFG-2100 series)

• Sweep mode with LINE and LOG (SFG-2100 series)

• Frequency output

• TTL/CMOS output

• Counter input (SFG-2100 series)

• External modulation input (SFG-2100 series)

GETTING STARTED

SFG-2000 Series User Manual

Front Panel

SFG-2100 series front panel

Main

Display

Power

Switch

Sweep Span/

Sweep Time

Speed Control

Log/Lin Selector

AM/FM

Control

Waveform

selection Key

DC Offset

Control

CMOS

Amplitude

Control

Entry

Keys

Amplitude/

Attenuation

Control

Counter

Input

Editing

Knob

TTL/CMOS

Output

Cursor

Keys

Waveform

Output

Main display

(7 segment)

Shows the waveform frequency, counter frequency, and duty cycle.

For SFG-2100 series only. In the counter mode, indicates that the leftmost digit (100MHz) is hidden but contains a real number. For counter details, see page40.

For SFG-2100 series only. In counter mode, indicates gate selection. For counter details, see page40.

TTL

Indicates that the TTL or CMOS output is enabled. For TTL/CMOS details, see page31.

For square wavefor m only. Indicates that the duty cycle is being edited. For square waveform details, see page25.

Indicates that the waveform output is attenuated by −20dB. For attenuation details, see page29.

SFG-2000 series front panel

Main

Display

Power

Switch

CMOS

Amplitude

Control

Waveform

selection Key

DC Offset

Control

Entry Keys

Amplitude/

Attenuation

Control

Editing

Knob

TTL/CMOS

Output

Waveform

Cursor

Keys

Output

For SFG-2100 series only. Indicates that the sweep mode is activated. For sweep details, see page35.

For SFG-2100 series only. Indicates that FM or AM mode is enabled. For modulation details, see page37 (AM) or page38(FM).

For SFG-2100 series only. Indicates that the counter mode is enabled. For counter details, see page40.

EXT

For SFG-2100 series only. Indicates that the external modulation input is used. For details, see page37 (AM) or page39(FM).

GETTING STARTED

SFG-2000 Series User Manual

Waveform selection key

Entry keys

Indicates the waveform shape: Sine, Square, and Triangle. For details, see page26.

Indicates that the Shift key is pressed.

Indicates the output frequency: MHz, kHz, or Hz.

Indicates the duty cycle unit. For duty cycle details, see page28.

WAVE

Selects the waveform shape: sine, square, and triangle. For details, see page26.

Enters frequency, duty cycle, and various parameters.

1 2

3 7

DUTY

−20dB

TTL

MHz

SWEEP

kHz

Hz/%

1.2MHz

MHz

37kHz

45% (in duty cycle mode) 45Hz (in frequency mode)

Enter duty cycle (page28).

Attenuate the waveform output by −20dB (page29).

Enables TTL/CMOS output (page31).

Deletes previous entry (backspace).

Selects Amplitude Modulation (page37).

Selects Frequency Modulation (page38).

Selects sweep mode (page35).

STORE

RECALL

Editing knob

Cursor keys

Wav ef orm

OUTPUT

50 Ω

output

TTL/CMOS

OUTPUT

output

Counter input

COUNTER

INPUT

Max AC 30Vrms

Stores the parameter setting (page42).

Recalls the parameter setting (page42).

Recalls the default parameter setting (page43).

Switches to counter mode (page40).

Accepts external modulation signal (page37-AM) or (page38-FM).

Increases (right turn) or decreases (left turn) the frequency or duty cycle.

Moves the editing point left or right in case of manual editing.

Outputs sine, square, and triangle waveform. BNC terminal, 50Ω output impedance.

Outputs TTL or CMOS output waveform, BNC terminal. For TTL/CMOS mode details, see page31.

Accepts signals for frequency counting. BNC, AC 30Vrms maximum. For counting mode details, see page40.

GETTING STARTED

SFG-2000 Series User Manual

Amplitude/ Attenuation control

DC offset control

CMOS amplitude control

Sweep speed control

Log/Linear sweep selector

AMPL

−20dB ADJ

OFFSET

TTL/CMOS

5V 15V

CMOS ADJ

SWEEP TIME

SLOW FAST

ADJ

CAL

TTL

LOG

LIN

Sets the sine/square/triangle waveform amplitude. Turn left (decrease) or right (increase).

When pulled out, attenuates the sine/square/triangle waveform amplitude by −20dB. The −20dB display turns On.

For details, see page29.

When pulled out, sets the DC offset level for sine/square/triangle waveform. Turn left (decrease) or right (increase). The range is −5V ~ +5V, in 50Ω load.

For details, see page30.

This knob becomes effective when the TTL/CMOS output is enabled (page31).

Selects TTL as output.

When pulled out, selects CMOS as output. Sets the CMOS output level. Turn left (decrease) or right (increase).

This knob is available in SFG-2100 series only. It becomes effective in sweep time mode.

Sets the sweep speed. Turn left (slow) or right (fast). The range is 1 ~ 30 seconds. For sweep details, see page35.

Sweep span control

AM/FM modulation control

Power switch

SWEEP SPAN

0MAX

AM %

FM Dev

This knob is available in SFG-2100 series only. It becomes effective in sweep mode and AM/FM mode.

In Sweep mode: Sets the sweep span. Turn left (narrow) or right (wide). The range is 1 ~ 100. For sweep details, see page36.

In AM/FM mode:

Sets the FM deviation (page38). Turn left (decrease) or right (increase). The range is over −50kHz ~ +50kHz, centered at 1MHz.

When pulled out, sets the AM depth (page37). Turn left (shallow) or right (deep). The range is 0 ~ 100%.

Turns the main power On/Off. For power up sequence, see page20.

Selects linear sweep.

When pulled out, selects

logarithmic sweep.

+ 20 hidden pages