Keithley 7077 Instruction Manual page 10

2 Operation
Figure 2-1 Model 7077 simplified schematic and crosspoint assignments ................................................................... 2-2
Figure 2-2 Simplified component layout ....................................................................................................................... 2-3
Figure 2-3 Single-ended switching example (using 4801 coaxial cable) ...................................................................... 2-4
Figure 2-4 Differential switching example .................................................................................................................... 2-4
Figure 2-5 Sensing example .......................................................................................................................................... 2-4
Figure 2-6 BNC connector identification ...................................................................................................................... 2-5
Figure 2-7 Backplane jumper configuration (factory default)....................................................................................... 2-7
Figure 2-8 Model 707 backplane configured for row expansion................................................................................... 2-7
Narrow matrix expansion (8 × 36) ............................................................................................................... 2-8
Figure 2-9
Wide matrix expansion (16 × 12)................................................................................................................. 2-9
Figure 2-10
Partial matrix example (16 × 24) ................................................................................................................. 2-9
Figure 2-11
Figure 2-12 Single card example ................................................................................................................................... 2-11
Figure 2-13 Multiple card system example ................................................................................................................... 2-12
Figure 2-14 Multiple switching matrix example – Model 707 ...................................................................................... 2-14
Figure 2-15 Multiple switching matrix example – Model 708 ...................................................................................... 2-15
Figure 2-16 Matrix/multiplexer system ......................................................................................................................... 2-16
3 Applications
Figure 3-1 Thick film resistor network testing .............................................................................................................. 3-2
Four-terminal Ω measurement ..................................................................................................................... 3-2
Figure 3-2
Figure 3-3 Voltage divider checks................................................................................................................................. 3-4
Figure 3-4 Transistor checking ...................................................................................................................................... 3-5
Figure 3-5 Transistor current gain checks ..................................................................................................................... 3-6
Figure 3-6 Common emitter characteristics of an NPN silicon transistor ..................................................................... 3-7
Figure 3-7 Transistor I
Figure 3-8 Transistor V
4 Service Information
Figure 4-1 Matrix card installation ................................................................................................................................ 4-3
Figure 4-2 Path resistance testing .................................................................................................................................. 4-6
Figure 4-3 Common mode offset current testing........................................................................................................... 4-7
Figure 4-4 Differential offset current testing ................................................................................................................. 4-7
Figure 4-5 Path isolation testing (guarded).................................................................................................................... 4-9
Figure 4-6 Differential isolation testing....................................................................................................................... 4-11
Figure 4-7 Common mode isolation testing ................................................................................................................ 4-11
Figure 4-8 ID data timing diagram .............................................................................................................................. 4-12
List of Illustrations
measurements ......................................................................................................................... 3-8
E
measurements...................................................................................................................... 3-9
BE
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