Keithley 2790, Справочное руководство

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Model 2790 SourceMeter
®
Switch System Reference Manual 8-3
Control source and event detection
The control source holds up operation until the programmed event occurs and is detected.
The control sources are described as follows:
• Immediate — With this control source, event detection is immediately satisfied
allowing operation to continue.
• External — Event detection is satisfied for any of the following three conditions:
• An input trigger via the Trigger Link line EXT TRIG is received.
• The front panel TRIG key is pressed. (The Model 2790 must be taken out of
remote before it will respond to the TRIG key. Use the LOCAL key or send
GTL over the bus.)
• Trigger command (*TRG or GET) is received over the bus.
Delay (auto or manual)
A programmable delay is available after event detection. It can be set manually or an auto
delay can be used. With auto delay selected, the instrument automatically selects a delay
period that will provide sufficient settling for function and autorange changes and multi-
phase measurements.
Normal measurement state
— With auto delay selected and the External or Bus control
source selected, the Model 2790 selects a delay based on the selected voltage range. The
auto delay period cannot be adjusted by the user. The auto delays are listed in
Table 8-1 .
With one of the other control sources selected, the auto delay is 0.000s for all functions
and ranges.
7702 Scanning
— When scanning, the nominal delay will be long enough to allow each
switching module channel relay to settle before making the measurement. When scanning,
the auto delay times in
Table 8-1 are valid for all control sources.