Keithley 2002 Repair Manual

Troubleshooting
2-83
Test 406.6 — Sample and hold circuit
Type
Pass/Fail
Fault message
Sample and hold
Description
This test is the same as test 406.5, but the value is stored for use in comparison calculation in
this test phase. The measurement compares the actual difference in the DAC voltages 406.1-
406.4 with that found via the sample and hold circuit tests 406.3-406.6.
Drawing reference
Analog Board; 2002-100
Components Q409, U402, U426, U428, and associated components.
Bit patterns
Bit pattern* Register
—U400—
01011101
—U811—
00001101
—U224—
00010111
—U432—
10000000
—U810—
00000011
—U206—
01110000
—U203—
10001110
—U411—
11111011
—U809—
11100111
—U207—
11001111
—U221—
11101001
—U406—
01001101
AD_STB
MUX_STB
R1_STB
R2_STB
*Bits associated with register IC terminals as follows:
QQQQQQQQ
87654321 87654321 87654321 87654321
IC pins: Q8=11, Q7=12, Q6=13, Q5=14, Q4=7, Q3=6, Q2=5, Q1=4.

Keithley 2002 Specifications

General

Brand	Keithley
Model	2002
Category	Multimeter
Language	English