analog_ambi
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Hi,
i simulated my pll using simulink n time domain and ended up with peculiar control voltage even with 60 deg/75deg PM.
Fig 1 shows the output of loop filter. Fig. 2 shows output after VDD saturation. I want my vco control voltage to slightly rise from 0 at t=0 and settle as if critically damped.
Is it due very small ref frequency and high N=2500
fref=400khz fout=1Ghz N=2500
i simulated my pll using simulink n time domain and ended up with peculiar control voltage even with 60 deg/75deg PM.
Fig 1 shows the output of loop filter. Fig. 2 shows output after VDD saturation. I want my vco control voltage to slightly rise from 0 at t=0 and settle as if critically damped.
Is it due very small ref frequency and high N=2500
fref=400khz fout=1Ghz N=2500