Keithley 2750 Service Manual

Power supply ....................................................................... 4-4
Display board ...................................................................... 4-6
Digital circuitry ................................................................... 4-7
Analog circuitry .................................................................. 4-9
Troubleshooting ....................................................................... 4-14
Display board checks ........................................................ 4-14
Power supply checks ......................................................... 4-14
Digital circuitry checks ..................................................... 4-15
Analog signal switching states .......................................... 4-16
No comm link error .................................................................. 4-24
5 Disassembly
Introduction ................................................................................ 5-2
Handling and cleaning ............................................................... 5-2
Handling PC boards ............................................................ 5-2
Solder repairs ...................................................................... 5-2
Static sensitive devices ....................................................... 5-3
Assembly drawings .................................................................... 5-3
Disassembly procedures ............................................................. 5-4
Case cover removal ............................................................. 5-4
Motherboard removal ......................................................... 5-4
Card cage removal .............................................................. 5-5
Front panel disassembly ...................................................... 5-5
Removing power components ............................................ 5-5
Instrument reassembly ............................................................... 5-6
Input terminal wire connections ......................................... 5-6
Power module wire connections ......................................... 5-7
6 Replaceable Parts
Introduction ................................................................................ 6-2
Parts lists .................................................................................... 6-2
Ordering information ................................................................. 6-2
Factory service ........................................................................... 6-2
Component layouts .................................................................... 6-3
A Accuracy and Optimization
Accuracy calculations ............................................................... A-2
Calculating DC characteristics accuracy ........................... A-2
Calculating AC characteristics accuracy ........................... A-2
Calculating dBm characteristics accuracy ......................... A-3
Calculating dB characteristics accuracy ............................ A-3
Additional derating factors ................................................ A-4
Optimizing measurement accuracy ........................................... A-4

Keithley 2750 Specifications

General

Interface	GPIB, RS-232, Ethernet
Switching Speed	Up to 500 channels/second
Maximum Voltage	300V
Operating Temperature	0°C to 50°C
Measurement Functions	DCV, ACV, DCI, ACI, 2-wire Resistance, 4-wire Resistance, Frequency, Temperature
Resolution	6.5 digits
Current	1A
Maximum Current	1A