Source Readback - Channels 13 And 25; Interlock - J106; General Purpose Terminal Blocks - J105, J107, And J108 - Keithley 2790 User Manual

Model 2790 SourceMeter
Source readback – channels 13 and 25
The actual output of the selected source can be verified by using source readback, which
routes the selected source back to the DMM of the 2790 for measurement. I-source and
V-source readback are explained in
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Interlock – J106
A 7751/7752/7753 module has an interlock to disconnect its I-source and V-source from
the rest of the switch matrix. In order to use the module sources, interlock must be
enabled. The interlock switch of a test station is connected to the J106 terminals of the
module. When the interlock switch is open (i.e., safety shield open), the sources cannot be
connected to the switch matrix. Details on interlock are provided in
NOTE
General purpose terminal blocks – J105, J107, and J108
There are quick-disconnect terminal blocks available to the user to provide access to various
switching module components. These are provided for general purpose test applications that
are not necessarily related to airbags.
J105 (matrix backplane and guard)
The backplane terminals provide access to the relay matrix backplane. The matrix backplane
is the primary "artery" for signal routing though the module.
The guard terminals are typically used for shielding when using the V-source and I/V con-
verter for high ohms measurements. Guard connections are explained in
J107 (source outputs and guard)
The I-source and V-source (7751/7753) are always on and can be accessed by the user at
J107. The programmed output is routed to these terminals.
The guard terminals are typically used for shielding when using the V-source and I/V
converter for high ohms measurements. Guard connections are explained in
®
Switch System User's Manual
Opening channel 22 and closing channels 21, 25, and 18 connects the I-source
sense resistor to the DMM of the Model 2790.
Closing channels 22, 21, 13, and 18 connects the V-source to the DMM of the
Model 2790.
The Interlock switch does not affect the output of J107. Voltage can still be present
at those terminals even if the interlock is disabled. See
blocks – J105, J107, and
Section 5.
J108" for additional details.
Section 5.
"General purpose terminal
Section 4.
Section 4.
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