Section 5: Pulse measure and pulse generator units
Model 4200A-SCS Parameter Analyzer Reference Manual
5-66
4200A-901-01 Rev. C / February 2017
Triggering
Triggering is used for the following operations:
•
(on page 5-66): Configure the Keithley pulse card for the trigger mode
(Continuous, Burst or Trig Burst) and use a software trigger to start pulse output.
•
(on page 5-67): Synchronize the pulse-measure operation of a
pulse generator card.
For each pulse in a test, a trigger pulse is sent to the trigger output. If you are using Segment Arb
waveforms, you can define if a trigger out is sent for each segment.
The 4220-PMU and 4225-PGU are trigger out only (no trigger in). These pulse cards use the internal
trigger bus for output synchronization when using any commands that require the
pulse_exec()
command to execute.
If you need to define a trigger in using a source-only pulse waveform (2-level or Segment Arb), you
can create a user test module (UTM) that uses the command set described in
(on page 13-6). This allows an external trigger (LPT command
pulse_trig_source
) to output a 2-level pulse (LPT commands
pulse_vhigh
and
pulse_vlow
)
or seg-arb (LPT command
seg_arb_define
). This allows for external triggering (a trigger input into
the card) that causes a burst of pulses to be output.
Triggering transition time must be <100 ns. Trigger output Level and Trigger In Level must be TTL.
Details on the trigger functions discussed in the following paragraphs are provided in the
(on page 13-1).
Basic triggering
The pulse output of a pulse card can be started by a software trigger. The LPT function for the
software trigger also sets the trigger mode. Enabled pulse generator channels will then output a
continuous string of pulses (continuous trigger mode), or a burst of pulses (burst or trig burst trigger
mode).
Software trigger source
To use a software trigger to start pulse output, the software trigger source must first be selected. The
(on page 13-155) function is used to select the software trigger source.
