Troubleshooting
4-5
Overall block diagram
shows an overall block diagram of the Model 2500. Circuitry may be divided
into two general areas:
•
Analog circuits — includes measurement circuits such as the I/V converter, mux,
and A/D converter, as well as voltage bias circuits.
•
Digital circuits — includes the microcomputer that controls the analog section,
front panel, and GPIB and RS-232 ports, as well as associated interfacing circuits.
Figure 4-1
Overall block diagram
Front Panel
Keypad
2 Line VFD
GPIB
RS-232
Digital I/O
Trigger Link
OPTO
Interface
Channel 1
Voltage Source Channel 1
±
10V,
±
100V
20mA Max
I/V Converter Channel 1
(8 Current Ranges
2nA - 20mA)
OUTPUT 1
INPUT 1
I/V Converter Channel 2
(8 Current Ranges
2nA - 20mA)
Voltage Source Channel 2
±
10V,
±
100V
20mA Max
A/D
OPTO
Interface
OUTPUT 2
INPUT 2
MC68332
Microprocessor
Channel 2
A/D
D/A
D/A
Содержание 2500
Страница 2: ...Contains Calibrating and Servicing Information Model 2500 Dual Photodiode Meter Service Manual...
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Страница 16: ...1 PerformanceVerification...
Страница 28: ...2 Calibration...
Страница 56: ...3 RoutineMaintenance...
Страница 59: ...3 4 Routine Maintenance Model 2500 Service Manual...
Страница 60: ...4 Troubleshooting...
Страница 74: ...5 Disassembly...
Страница 81: ...5 8 Disassembly Model 2500 Service Manual...
Страница 82: ...6 ReplaceableParts...
Страница 93: ...6 12 Replaceable Parts Model 2500 Service Manual...
Страница 94: ...A Specifications...
Страница 98: ...B CalibrationReference...
Страница 108: ...C CalibrationProgram...
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Страница 121: ...Keithley Instruments Inc 28775 Aurora Road Cleveland Ohio 44139 Printed in the U S A...