Keithley 7072 Instruction Manual page 11

3 Applications
MEASUREMENT CONSIDERATIONS .........................................................................................................
2.24
Magnetic Fields ......................................................................................................................................... 2-24
Electromagnetic Intcrfcrencc (EMI). .........................................................................................................
2-25
Ground Loops.. ..........................................................................................................................................
2-25
Keeping Connectors Clean ........................................................................................................................
2-26
Noise Currents Caused by Cable Flexing.. ................................................................................................ 2-26
Shielding.. .................................................................................................................................................. 2.26
Guarding.. ..................................................................................................................................................
2-28
Matrix Expansion Effects on Card Spccilications.. ................................................................................... 2-29
INTRODUCTION.. .............................................................................................................................................
3. I
CV MEASUREMENTS.. ....................................................................................................................................
3-l
Stand AIonc System Configuration.. ........................................................................................................... 3-l
Computerized System Configuration ..........................................................................................................
3-l
Optimizing CV Measurement Accuracy .......................................................... ........................... ......... .... 3-4
Basic CV Test Procedure.. ...........................................................................................................................
3-4
Typical CV Curves ......................................................................................................................................
3-4
SEMICONDUCTOR TEST MATRIX ...............................................................................................................
3-6
System Configuration.. ................................................................................................................................ 3-6
Testing Common-Source Characteristic of FETs.. ...................................................................................... 3-8
RESlSTIVITY MEASUREMENTS ................................................................................................................... 3-9
Test Configuration ............................................................................................ .......................................... 3-9
Test Procedure.. ...........................................................................................................................................
3-9
Resistivity Calculations.. ........................ ................. ..........................................................
... .................. 3-9
SEMICONDUCTOR
PARAMETER ANALYSIS ,.,..,..................................................................,..., .............. 3.12
System Configuration.. ..............................................................................................................................
3-12
Cable Connections.. ................................................................................................................................... 3- I3
SPA Mcasuremcnt Considerations.. ..........................................................................................................
3- I.5
Typical Test Proccdurc.. ............................................................................................................................
3.15
4
Service Information
INTRODUCTION
............................................................................................................................................... 4-I
HANDLING AND CLEANING PRECAUTIONS ............................................................................................ 4-I
PERFORMANCE VERIFICATION.. .................................................................................................................
4 -1
Environmental Conditions.. ......................................................................................................................... 4-l
Recommended Test Equipment.. ................................................................................................................. 4-l
Relay Testing.. .............................................................................................................................................
4-2
Offset Current Verification.. ........................................................................................................................
4-3
Path Isolation Verification.. .........................................................................................................................
4-S
Path Resistance Verification.. ...................................................................................................................... 4-7
SPECIAL HANDLING OF STATIC-SENSITIVE
DEVICES ........................................................................ 4 -IO
TROUBLESHOOTING
.................................................................................................................................... 4-10
Recommended Equipment ......................................................................................................................... 4-10
Using the Extcndcr Card ........................................................................................................................... 4-10
Troubleshooting Prwxdure ....................................................................................................................... 4-10
PRINCIPLES OF OPERATION.. ..................................................................................................................... 4 I2
Block Diagram.. ......................................................................................................................................... 4-12
ID Data Circuits.. ....................................................................................................................................... 4 I3
Relay Control.. ...........................................................................................................................................
4 I3
Powcr-on Safeguard .................................................................................................................................. 4-l 3
Isolator Relays ...........................................................................................................................................
4 I3
REAR SHIELD.. ................................................................................................................................................
4-13
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