Posted on Jun 29, 2012 4110
A single monostable multivibrator delays a pulse train by a variable amount; nonetheless, this amount can be no less than the minimum allowed pulse width fwÂ· The exclusive-OR gate, IC1, generates a short pulse following every leading or falling edge of the input waveform. These pulses cause one-shot IC2 to produce a negative-going pulse with a duration equal to the desired time delay tp, which you set by adjusting potentiometer R.
Flip-flop IC3 then creates a delayed replica of the input pulse hy latching the Ql output of IC2 between positive-going transitions. You can independently control the output-pulse duration hy cascading a second one shot with the first.