Keithley 194 Instruction Manual page 10

6.7
I/O (Input/Output) Circuitry.
.............................
6.7.1
I/O Block Diagram. ....................................
6.7.2
Bus Buffering ..........................................
6.7.3
Display and Keyboard Interface ..........................
6.7.4
Serial and NVRAM Control
.............................
6.75
Analog Output Interfacing ..............................
6.8
POWER SUPPLIES..
.....................................
6.8.1
Power Supply Block Diagram.
...........................
6.8.2
Power LineInput .......................................
6.8.3
Digital Supplies ........................................
6.8.4 Analog Supplies
.......................................
6.9
DISPLAYBOARD ........................................
6.9.1
Block Diagram of Display Board .........................
6.9.2
Circuit Description
.....................................
SECTION -/-MAINTENANCE
.................
.................
.................
.................
.................
.................
.................
.................
.................
.................
.....
.....
......
......
......
......
......
......
......
6-l')
6.1Y
6-21
h-21
6-21
h-21
6.2~1
b-21
h-22
h-23
h-23
h-21
6-24
h-25
7.1
7.2
7.3
7.3.1
7.3.2
7.4
7.4.1
7.4.2
7.5
ix.1
7.5.2
7.5.3
7.5.4
7.5.5
7.5.6
7.6
7.7
7.7.1
7.7.2
7.7.3
7.7.4
7.7.5
7.8
7.8.1
7.8.2
7.8.3
7.8.4
7.8.5
7.8.6
7.8.7
7.8.8
7.8.9
7.8.10
7.9
7.10
7.11
INTRODUCTION
..............................................................................
7.1
LINE VOLTAGE SELECTION
...................................................................
7-l
FUSE REPLACEMENT
.........................................................................
7-2
Line Fuse Replacement .......................................................................
7-2
Digital Supply Fuse Replacement
............................................................. 7-2
OPTION INSTALLATION.. ....................................................................
7-2
Installation Procedures .......................................................................
7.2
Module Recognition Programming
............................................................ 7-6
CALIBRATION
........................................................................... ...
7-h
Recommended Calibration Equipment
......................................................... 7-h
Environmental Conditions,
......................................................... ......... 7-0
Warm-up Period .............................................................................
7-i
Front Panel Calibration
....................................................................... 7-7
IEEE-488 Bus Calibration .....................................................................
7-X
Input Amplifier Frequency Compensation Adjustment
.........................................
7-10
SPECIAL HANDLING OR STATIC-SENSITIVE
DEVICES ........................................
7-12
DISASSEMBLY ...............................................................................
7-13
Top and Bottom Cover Removal ..............................................................
7-13
Circuit Board Removal and Replacement
................................................... .. 7-15
Case Disassembly
.......................................................................... 7-20
Rear Panel Disassembly
.....................................................................
7-20
Front Panel Disassembly ....................................................................
7-20
TROUBLESHOOTING ........................................................................
7.25
Recommended Test Equipment
..............................................................
7-2.5
SelfTest ...................................................................................
7-25
Troubleshooting
Sequence. .................................................................. 7-27
Power Supply Checks .......................................................................
7-27
Microcomputer
.............................................................................
7.27
Display Board..
............................................................................
7-27
l/O Board ..................................................................................
7-27
Analog Circuitry Checks ....................................................................
7~33
A/D Converter Checks ......................................................................
7~3.1
A/D Board Digital Circuitry
Checks .......................................................... 7-33
FAN FILTER CLEANING/REPLACEMENT
...................................................... 7-38
Z OUTPUT HIGH LEVEL MODIFICATION
................................................. .. 7-38
CIRCUITBOARDJUMPERLOCATIONS .......................................................
7-38
SECTION 8--REPLACEABLE PARTS
8.1
INTRODUCTION .,,....,...........,...........,,,........................
8.2
ELECTRICAL PARTS LIST ,..........,,,.......,...,.........,,........,....
:::::::::::::::::: HH::