Connections
2-9
•
The Model 6430 will perform to rated specification with up to 1V drop per source lead
on the 100µA through 100mA ranges. On the 10µA range and below (when using the
Remote PreAmp), the allowable voltage drop in each source lead is limited as follows:
Guarding methods
Cable guard
Use the high-impedance (cable) guard connection scheme shown in Figure 2-4 for the fol-
lowing source-measure condition:
•
Test circuit impedance is >1G
Ω
.
Cable guard is always available at the Remote PreAmp. If not using the Remote PreAmp,
use the V,
Ω
GUARD banana jack on the mainframe with CABLE guard selected. See
Guard
selection
to select cable guard.
A test fixture is typically used when testing high-impedance devices. The test fixture reduces
noise and protects the user from a potentially hazardous voltage on the guard shield (or plate).
See
Section 5, Guard
for details on using guard.
Note that the test fixture chassis is connected to In/Out LO to reduce noise.
Current range
Maximum allowable resistance
per source lead
10µA
1µA
100nA
10nA
1nA
100pA
10pA
1pA
10
Ω
50
Ω
500
Ω
5k
Ω
50k
Ω
1M
Ω
50M
Ω
1G
Ω
Guard
Shield
Triax Cable
Test Fixture
HI
LO
Connect to earth
safety ground using
#18 AWG wire or
larger
DUT
WARNING Guard is at the same voltage level as
input/output high. Therefore, if a
hazardous voltage (
≥
42V peak) is
present on input/output high, it is also
present on the guard terminals of the
Remote PreAmp and mainframe.
6430
REMOTE
PreAmp
SENSE
MAINFRAME
Connect to
REMOTE PreAmp
connector on rear
panel of mainframe
Guard
IN/OUT
HIGH
Preamp Cable*
KEITHLEY
*Keithley part number: CA-176-1D.
Figure 2-4
High-impedance
guarding
Содержание 6430
Страница 26: ......
Страница 32: ......
Страница 78: ...2 14 Connections ...
Страница 98: ...3 20 Basic Source Measure Operation ...
Страница 138: ...5 30 Source Measure Concepts ...
Страница 156: ...6 18 Range Digits Speed and Filters ...
Страница 168: ...7 12 Relative and Math ...
Страница 176: ...8 8 Data Store ...
Страница 202: ...9 26 Sweep Operation ...
Страница 248: ...11 22 Limit Testing ...
Страница 310: ...16 6 SCPI Signal Oriented Measurement Commands ...
Страница 418: ...17 108 SCPI Command Reference ...
Страница 450: ...18 32 Performance Verification ...
Страница 477: ...A Specifications ...
Страница 489: ...B StatusandErrorMessages ...
Страница 498: ...B 10 Status and Error Messages ...
Страница 499: ...C DataFlow ...
Страница 503: ...D IEEE 488BusOverview ...
Страница 518: ...D 16 IEEE 488 Bus Overview ...
Страница 519: ...E IEEE 488andSCPI ConformanceInformation ...
Страница 523: ...F MeasurementConsiderations ...
Страница 539: ...G GPIB488 1Protocol ...
Страница 557: ......