Keithley 2002, User Manual

Page: 80 / 366

Front Panel Operation
2-63
The BENCH RESET condition arms the Model 2002
and places multimeter operation at point A in the flowchart,
where it is waiting for a Trigger Link trigger. Note that since
both the arm layer and scan layer are programmed for Imme-
diate Source, operation immediately drops down to the mea-
sure layer at point A.
Pressing STEP takes the Model 7001/7002 out of the
idle state and places operation at point B in the flowchart.
Since both the arm layer and scan layers are programmed for
Immediate Spacing, operation drops down to the Channel
Layer at point B.
Since Channel Trigger Source is set to Source, the
scan does not wait at point B for a trigger. Instead, it bypass-
es “Wait for Trigger Link Trigger” and closes the first chan-
Figure 2-29
Operation mode for semi-synchronous Trigger Link example
Idle
Bypass
B
Wait for
Trigger Link
Trigger
Scan
Channel
C
Pull Trigger
Line Low
D
No
Scanned
10
Channels
?
Yes
7001or 7002
Make
Measurement
Made
10
Measurements
?
2002
Press STEP to start scan
Arm
A
Wait for
Trigger Link
Trigger
E
Release,
Trigger Line
F
No
Yes
A
B
C
nel (point C). Note that the Bypass is in effect only on the
first pass through the model.
After the relay settles, the Model 7001/7002 pulls
down the Trigger Link trigger line (point D). Since the in-
strument is programmed to scan ten channels, operation
loops back up to point B, where it waits for an input trigger.
Note that Bypass is no longer in effect.
and Remember that the Model 2002 operation is
at point A waiting for a trigger. When the trigger line is
pulled low by the Model 7001/7002, the leading negative-
going edge triggers the Model 2002 to measure DUT #1
(point E). Note that the multimeter holds the trigger line low.
After the measurement is complete, The Model 2002
releases the trigger line (point F) and then loops back to point
A where it waits for another input trigger.
D
E F