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Simulators >> RF Simulators >> strange behavior of pll pss simulation
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Message started by zczc999 on Mar 29^th, 2015, 3:45am

Title: strange behavior of pll pss simulation
Post by zczc999 on Mar 29^th, 2015, 3:45am

Hello everyone,

I have a very strange pss simulation that the pll charge pump voltage suddenly becomes unstable after locking. But if I use transient simulation, I don't see this change. (pink plot is from transient simulation, red plot is pss)

Also the PLL feedback clock begins to lose locking. Then I have convergence problem.

What is the possible reason for this ?

Title: Re: strange behavior of pll pss simulation
Post by Ken Kundert on Mar 30^th, 2015, 11:54am

Please do not ask simulation questions in a design board. Doing so makes it less likely that your question will be answered.

You should not select 'oscillator'. A PLL in lock is a driven circuit.

-Ken