Phase shift a TTL for edge triggering

Thread Starter

Laserdan

Joined Dec 29, 2020
1
Hi,

I am running an experiment that requires an ultrasonic pulse (cleaned up with a mono stable multivibrator) to be triggered on the positive slope of an optical chopper’s (used to modulate a laser beam) TTL square wave signal. I have the triggering down, but I need to shift the TTL signal’s phase to offset my ultrasound pulse with my laser pulse. The TTL runs at frequencies between 0-3000 Hz at a 50% duty cycle.

Does anyone have a simple solution to achieve this phase shift? Could this be done with passive components, or perhaps an op amp or NAND Gate?
Thanks,
Dan
 

MrChips

Joined Oct 2, 2009
22,531
Welcome to AAC!

Use can use a pair of monostable multivibrators such as a single 74LS123 to create a new pulse following a delay.

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crutschow

Joined Mar 14, 2008
26,035
A phase-shift of the leading and trailing pulse edges could also be generated with an RC delay into a Schmitt-trigger circuit (e.g. 74x14).
Such a circuit will basically maintain the pulse-width of the original signal.
 
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