variable frequency phase shifter
I am designing a three-channel pulse circuit with a range of 1Hz to 1MHz. It only puts out square waves and I'm trying to think of the simplest way to allow the phase of the outputs to be adjusted between 0 and 180 degrees. I found a simple Op-amp circuit to do it but I'm not sure how that would work when the input frequency can be changed. Is there any kind of circuit (or IC) which can do this but can do the shift proportional to the frequency?