Agilent Part No Microfiche Part No September
Certification
Safety Considerations
Symbol Description
Safety Symbol Definitions
Printing History
Table of Contents
Principles Of Operation
Diagrams
Replaceable Parts
Backdating
Instrument Identification
Scope Organization
Chapter Description
Introduction
Manual Revisions
Related Documents
Firmware Revisions
Change Sheet
Conventions
Safety Considerations
Electrostatic Discharge
Tests
Introduction
Test Equipment Required List of Equipment
Current-Monitoring Resistor
Electronic Load
General Measurement Techniques
Programming The Tests General Considerations
Performance Test Record Sheets
Programming Parameters
Performance Tests
Operation Verification Tests
Constant Voltage CV Tests
Constant Voltage CV Test Setup Verification
Voltage Programming and Readback Accuracy
Constant Voltage CV Tests Action Normal Result
CV Load Effect
CV Source Effect
CV Noise Pard
Transient Response Waveform Verification
Transient Recovery Time
Constant Current CC Tests Action Normal Result
Constant Current CC Tests
Current Programming and Readback Accuracy
CC Noise Pard
CC Load Effect
CC Source Effect
CC Load Effect Test Setup Verification
CC rms Noise Test Setup Verification
Averaging the CC Measurements
Test Facility
Performance Test Record Form
Spec
Results
Uncertainty
Vout 0.5mV Vout + 0.5mV 900 nV
Vout 1mV Vout + 1mV
Vout 1.7mV Vout + 1.7mV
Vout 2.3mV Vout + 2.3mV
Troubleshooting
Introduction Localizing the Problem
Chapter Organization
Topic Information Given
Test Equipment Required
Troubleshooting Procedures Power-On Selftest
EE Chksm
FP ROM
PRI Xram
PRI Iram
Troubleshooting Test Points
Troubleshooting Charts
Chart Trouble or Circuit
Bias and Reference Supplies
Overall Troubleshooting Sheet 1
Overall Troubleshooting Sheet 2
Overall Troubleshooting Sheet 3
Overall Troubleshooting Sheet 4
No Display Troubleshooting
OV Will Not Fire Troubleshooting
OV At Turn-On Troubleshooting
Output Held Low Troubleshooting Sheet 1
Output Held Low Troubleshooting Sheet 2
Output Held High Troubleshooting
DAC Circuits Troubleshooting
DAC Test Waveforms Troubleshooting
CV/CC DAC and Amplifier Circuit Troubleshooting
10. Serial Down Troubleshooting Sheet 1
10. Serial Down Troubleshooting Sheet 2
11. Secondary Interface Down Sheet 1 Troubleshooting
11. Secondary Interface Down Sheet 2 Troubleshooting
12. Slow Downprogramming Troubleshooting
A3 FET Board Troubleshooting
CV/CC Status Annunciators Troubleshooting
FET Troubleshooting Chart Procedure Result
Static Troubleshooting
Dynamic Troubleshooting
13. A3 FET Board Test Waveforms Troubleshooting
Allocate L$52 Output 705*IDN? Enter 705L$ Disp L$ 50 END
Signature Analysis Introduction
Agilent Technologies ,6681A,O,fA.01.05sA.01.04pA.0l.02
Front Panel Test Connector A1J3
Pins Description
Test Headers
Valid A2U106 ROM Firmware Revision A.01.06
Primary Interface SA Test
16. Signature Analysis Connections, Sheet 1 Troubleshooting
Valid A1U4 ROM Firmware Revision A.01.07
Valid A5U504 ROM Firmware Revision A.01.04
Secondary Interface SA Test
Calibration Password
Post-Repair Calibration When Required
Inhibit Calibration Jumper
Restoring Factory Calibration Constants
Initialization I or Factory Preset Replacement F? F
Initialization I or Factory Preset Replacement F?
Eeprom Initialization
Clear Screen
END Select
Case Else
END if
Else
Stop
Case
1530
Tools Required
Disassembly Procedures
Return
END
Removing Protective RFI Shield Galvanized Sheet Metal
Top Cover
Gpib Board
A5 DC Rail Assembly
A4 AC Input Assembly
A6 Bias Assembly
A3 FET Board
Front Panel Assembly
A10 Control Assembly
S1 Line Switch
A1 Front Panel Board
A1G1 and A1G2 Rotary Controls
A1DSP1 LCD Display
A1KPD Keypad
Output Bus Boards A7, A81 and A9 & Chassis Components
Page
19 -Inch Front Panel Frame Assembly Troubleshooting
20 -Inch Front Panel Frame Assembly Troubleshooting
21. Assembly A10, Exploded View Troubleshooting
22. Assembly A10, Exploded View 6680A, 6681A Troubleshooting
Page
24. Three-Phase Line Choke Subchassis Wiring Troubleshooting
25 Volt Fan Transformer Troubleshooting
Principles Of Operation
A2 Gpib Board
A10 Control Board
A1 Front Panel Assembly
Secondary Interface P/O A10 Board
AC Calibration of Imon
Principles Of Operation
A5 DC Rail Board
A4 AC Input Board
Output Circuits
ST Stage of the FET H-Bridge Configuration
Page
Reading the Tables
Assembly See
Part Reference Designators
Part Description Abbreviations
Main Chassis, Replaceable Parts
How to Order Parts
Ref. Desig Agilent Part No Description
BUS BAR Buss BAR Block BUSS/FET Block
SENSOR-MOISTURE TERM-BLK-4 POS Connector
FAN Finger Guard
Phase Line Choke
FAN-TUBEAXIAL
TRIM-SIDES
A1 Front Panel Board, Replaceable Parts
Front Panel Board LED Assy, Replaceable Parts
Mechanical Parts
DIO-PWR Rect
DIO-SWITCHING
CORE-SHLD-BEAD
CORE-MAGNETIC
Q301, 302, 303 1855-0859
Replaceable Parts
A4 AC Input Assembly, Replaceable Parts
10. A6 Bias Assembly, Replaceable Parts
Heat SINK-TRANSISTOR 1854-0828 Assy
FU-SUBMIN 4A
XFMR-BIAS
XFMR- Gpib
Heat SINK-LM317T Regulator Assy
Heat SINK-UA7805UC Regulator Assy
12. A7 Fast Sense Assembly, Replaceable Parts
Wire KIT
Fast Sense PC Assembly
FU-SUBMIN 15A
Power Modfet
FU-SUBMIN 7A
Xstr PNP
Replaceable Parts
C588 0160-4799 CAP 2.2pF 5% C589 6680A, 6681A
Phone Receptable
DIO GEN PRP
FET P-CHAN
NETWORK-RES SIP
Replaceable Parts
Replaceable Parts
RES 45K
RES2.2M
IC-REG TL7702BCP
RES 10K
IC OP AMP
IC-VOLTAGE REG
IC MC74HC138N
PRGMD-IC, SEC
IC-CONVERTER,DIA
IC-LINEAR
Diagrams
Summary of Chapter Contents Function Description See
AD O--AD7
Signal Name Mnemonics Description A0--A15
ANA0--ANA7
D0D7
DC Rail Board
AC Input Board
Bias Board
A10 Control Board
A3 FET Board
CV Control Sheet
CC Control Sheet
General Schematic Notes
General Schematic Notes
DP Control Sheet
Common
Test Point Waveforms for Table Diagrams
Circuit Board Cabling Diagram Diagrams
Page
A1 Front Panel Board, Schematic Diagram
LED Board, Component and Test Point Location
A2 Gpib Board, Component Location
A2 Gpib Board, Schematic Diagram
A3 FET Board, Component and Test Point Location
10. A3 FET Board, Schematic Diagram sheet 1
10. A3 FET Board, Schematic Diagram sheet 2
11. A4 AC Input Board, Component and Test Point Location
12. A4 AC Input Board, Schematic Diagram
13. A5 DC Rail Board, Component and Test Point Location
14. A5 DC Rail Board, Schematic Diagram
15. A6 Bias Board, Component and Test Point Location
16. A6 Bias Board, Schematic Diagram Sheet 1of
16. A6 Bias Board, Schematic Diagram Sheet 2
17. Power Mesh, Schematic Diagram, Models 6680A, 6681A Only
Page
19. A7 Snubber Board, Component Location
21. A8 Fast Sense Board, Component Location
23. A9 Down Programming/Slow Sense, Component Location
24. A9 Down Programming/Slow Sense, Schematic Diagram
25. A10 Control Board, Component and Test Point Location
26. A10 Control Board, Schematic Diagram Sheet 1
26. A10 Control Board, Schematic Diagram Sheet 2
26. A10 Control Board, Schematic Diagram Sheet 3
26. A10 Control Board, Schematic Diagram Sheet 4
Model 6681A Model 6684A
Serial Numbers Change Model 6680A Model 6683A
Model 6682A
Backdating
-14 Al0 Control Board
-9 A5 DC Rail Board
-8 A4 AC Input Board
-6 A2 Gpib Board
Ref Desig Agilent Part No Description
Table A-1. A2 Gpib Parts List
IC Drom Gpib
Figure A-1. A2 Gpib Component Parts List Backdating
Index
Index
Error code
Message
104
Signal name
Troubleshooting
