Part Number: DAC37J84 Tool/software: Datasheet mentions "as the P*M ratio increases, the charge pump current needs to be increased accordingly". I'm assuming this should read "P*M product" not "P*M ratio". Datasheet describes "extreme" example of P*M = 400 needing external loop filter since we exceed maximum charge pump current. I have P*M = 48 (/4 prescalar, /8 M divider), would this require external loop filter? Datasheet indicates that P*M =8 requires 600uA. Max charge charge pump current is 1550uA, so it seems P*M > ~16 would require external filter, is this right? Is there a tool for modeling the loop? If not, is the transfer function of the VCO available so that we can model it? Seems that I would need to tailor the zeros-poles to my particular P*M.
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