raja.cedt
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Hello, Looks like some thing seriously went wrong in the filter design, that's why some weird start-up, it is dangerous some times just because vctl is saturating and may turn of charge pump. But frequency settling looks okay, though there is some ringing (some part is cycle slipping). Did you modified your charge-pump current (as i suggested earlier), though you don't have power margin just try that (some how reduce the BW) and see the response. Since you have 33.33khz BW, your loop should settle in 4*tau, which is around 120us but your settling looks pretty faster than this.
Even if you have any problem with settling, due to less Phase margin magnitude response might have few db peaking which amplifies your jitter, so it all depends on which kind application you are targeting.
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