Phase Shift for 75% duty cycle signal

Thread Starter

doctorneocortex

Joined Mar 17, 2019
2
Hello all,

I have a 25% duty cycle signal with frequency range 20 kHz-40 kHz. I need a phase shift relative to a positive edge of a square wave with half frequency of input signal. I am attaching a visualization for input signal and relative signal. Any help would be greatly appreciated. Thank you.
 

Attachments

MisterBill2

Joined Jan 23, 2018
7,315
Use a PLL and a divide by 4 counter to synchronize it with the existing signal, That will give you phases at in phase, 25%, 50%, and 75% to select. I think that is what you are asking for but really the question is not very clear. In fact, I found it very confusing even looking at the picture.
 

danadak

Joined Mar 10, 2018
4,057
In the posted timing pic are these two signals sync or async ?

A PWM with compare registers can set the phase relationship to its clock,
in this case the signal you want to phase shift.

Do you want to do this with a processor or discrete logic ?

Lastly do you want edge relationship to have no latency ?



Regards, Dana.
 

Thread Starter

doctorneocortex

Joined Mar 17, 2019
2
These two signals are async. I should use discrete logic or analog not any microcontrollers.
No, I dont need edge relationship to have no latency.

In the posted timing pic are these two signals sync or async ?

A PWM with compare registers can set the phase relationship to its clock,
in this case the signal you want to phase shift.

Do you want to do this with a processor or discrete logic ?

Lastly do you want edge relationship to have no latency ?

Regards, Dana.
 

danadak

Joined Mar 10, 2018
4,057
So just to be clear the positive edge of the square wave marks the reference
for delayed start of the 25% DC pulse train. But the square wave is fixed freq,
not so the pulse.

If thats the case there exists only one freq where each successive square positive
edge generates the same position of the delayed 25% DC pulse train.....? Right ?


Regards, Dana.
 

MisterBill2

Joined Jan 23, 2018
7,315
If the two signals are indeed asynchronous, then you do not get a phase shift, because a phase shift is between signals of the same frequency that are synchronous.
The result is that we need a greater explanation to avoid making a thread of, at best, random conjectures. Once there is an adequate understanding of the desired results this site can deliver great answers. Until then you get "best guesses."
 
Top