GW Instek SFG-1000 User Manual

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.

Good Will Instrument Co., Ltd.

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

Table of Contents

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

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

Safety Guidelines...................................................5

GETTING STARTED............................................................8

Technical background.............................................9

Lineup/Features....................................................11

Front Panel...........................................................12

Rear Panel.............................................................15

Set Up...................................................................16

Operation Shortcuts..............................................18

SINE/SQUARE/TRIANGLE WAVE.....................................19

Activate waveform.................................................20

Set Frequency........................................................20

Set Amplitude.......................................................22

Set Duty Cycle (Square Waveform).........................23

Set Offset..............................................................23

TTL OUTPUT....................................................................25

Activate TTL..........................................................25

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

Set Duty Cycle.......................................................27

APPLICATION EXAMPLES................................................28

Reference Signal for PLL System............................28

Trouble-Shooting Signal Source.............................28

Transistor DC Bias Characteristics Test..................29

Amplifier Over-Load Characteristic Test.................30

Amplifier Transient Characteristics Test.................30

SFG-1000 Series User Manual

Logic Circuit Test..................................................32

Impedance Matching Network Test.......................32

Speaker Driver Test...............................................33

FAQ.................................................................................34

APPENDIX.......................................................................35

Fuse Replacement................................................35

Specification........................................................37

Declaration of Conformity.....................................39

INDEX.............................................................................40

Safety Instructions

SAFETY INSTRUCTIONS

This chapter contains important safety instructions that you must follow when operating SFG-1000 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-1000 series.

Safety Symbols

These safety symbols may appear in this manual or on SFG-1000 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-1000 series or to other properties.

Attention Refer to the Manual

Earth (ground) Terminal

Safety Guidelines

General Guideline

CAUTION

• Do not place any heavy object on SFG-1000 series.

• Avoid severe impacts or handling that leads to damage.

• Do not discharge static electricity to SFG-1000 series.

• Use only mating connectors, 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-1000 series unless you are

qualified as service personnel.

Safety Instructions

• 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.

Storage Environment

• Location: Indoor

• Relative Humidity: < 70%

• Temperature: −10°C to 70°C

Power cord for the United Kingdom

When using SFG-1000 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 or coloured Green or Green & Yellow. 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.

SFG-1000 Series User Manual

GETTING STARTED

This chapter describes SFG-1000 series in a nutshell, including main features and front/rear/display introduction. Follow the Set Up section to properly install and power up SFG-1000 series.

SFG-1000 series overview

Panel introduction

Setup

Technical background.............................................9

Series lineup........................................................11

Main features.......................................................11

Main Display........................................................12

Entry keys.............................................................13

Others..................................................................14

Rear Panel............................................................15

Tilt stand..............................................................16

Power up..............................................................17

Functionality check...............................................17

Quick reference

Operation Shortcuts.............................................18

Getting Started

Technical background

Traditional function generators

DDS methodology

SFG-1000 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.

SFG-1000 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

28bit

Table

ROM/RAM

12bit

28bit

Digital-Analog

Converter

Low-Pass

Filter

Output (fo)

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.

Getting Started

Lineup/Features

Series lineup

Features

Lineup

Frequency

Offset TTL

output

−40dB attn.

Voltage

display

SFG-1003 SFG-1013

3MHz ● ● ● 3MHz ● ● ● ●

Main features

Performance • High resolution using DDS technology

• High frequency accuracy: ±20ppm

• Low distortion: −55dBc @ ≤200kHz

• High resolution 100mHz

Features • Digital user interface with 6-digit LED display

• Various output waveforms: Sine, Square, and Triangle

• TTL output

• Amplitude control

• −40dB attenuation

• Duty control

• Variable DC offset control

• Output On/Off control

• Voltage display (SFG-1013)

• Output overload protection

―

Interface • Frequency output

• TTL output

SFG-1000 Series User Manual

Front Panel

Main Display

7 segment LED

TTL indicator

Waveform indicator

Frequency indicator

Voltage indicator (SFG-1013 only)

−40dB indicator (SFG-1013 only)

Shows frequency and voltage.

Indicates that the TTL output is enabled. For details, see page25.

Indicates the waveform shape: Sine, Square, and Triangle.

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

Indicates Voltage unit: mV, or V. For voltage measurement detail, see page22.

Indicates −40dB attenuation is activated. For details, see page22.

Entry keys

(9,0)

Getting Started

Waveform key

TTL activation

Numerical keys

Frequency unit selection

Cursor selection

WAVE

SHIFT

Selects the waveform: sine, square, and triangle. For details, see page20.

Activates TTL output. For details,

WAVE

see page25.

Specifies frequency.

Specifies the frequency unit:

MHz, kHz, or Hz.

Moves the cursor (frequency editing point) left or right. For details, see page21.

−40dB attenuation (SFG-1013 only)

Frequency / Voltage display selection (SFG-1013 only)

Shift key

Output On/Off key

SHIFT

Attenuates amplitude by −40dB.

For details, see page22. Key operation is for SFG-1013 only.

Switches the display between frequency and voltage. For details, see page22. For SFG-1013 only.

Selects the 2nd function associated to the entry keys. The LED lights when Shift is activated.

Turns the output On/Off. The LED lights when the output is On.

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