input/output characteristics of the PFD

BigBoss said:

PFD has a transfer function being as Current/Phase Difference.Apply two square wave signal generator with same frequency and with same duty cycle, do a transient simulation.Fix one of them and change the phase of the second one from -PI to PI by small phase differences-for instance 1 degree- and observe current output and draw this transfer function in Cadence.You will see deadzone.

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Engineer4ever said:

First of all, thanks for your reply

Does your answer mean that I will memorize the change in the PFD o/p versus every phase difference and tabulate the results then draw them on Excel for example? I thought about that but I think there might be a way to draw the PFD cs/s directly on cadence, using sweeping on the phase difference, but I still don't know how to draw it versus the o/p.

If that's not what you mean, would you please explain a little more?

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BigBoss said:

If you draw "Current versus Sweeping Variable" , the deadzone will be visible

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