Pulsewidth

pulsewidth trigger diagrams, analogue and TTL

The "Pw" programmable value defines the width of the analogue channel pulse that must be reached (or conversely not reached) for trigger detection. Very useful in applications where the trigger is in embedded within a background of electrical noise, as the signal to trigger on is often of very different duration.

Pulse width operation can also be used with digital (TTL) signal triggers which are normally injected via the boards dedicated trigger input connector
(see right-hand pair of diagrams above).

  Mi/M2i cards PCI.248/258  
Pulse > Pw x x After crossing the defined trigger level, a trigger will occur at the end of the programmed pulsewidth. Further crossings of the trigger level within the programmed pulsewidth are ignored. This may be used to avoid multiple triggers on noisy signals.
Pulse < Pw x - The signal must cross the trigger level a second time in the programmed pulsewidth. Could be used to trigger on glitches and spikes.
TTL > Pw x x A TTL pulse on the external trigger connector that is longer than the programmed pulsewidth.
TTL < Pw x - A TTL pulse on the external trigger connector that is shorter than the programmed pulsewidth.