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Design >> Analog Design >> Reducing resistors in a loop filter of a type II PLL to hasten locking
https://designers-guide.org/forum/YaBB.pl?num=1502207512

Message started by Hercules Poirot on Aug 8^th, 2017, 8:51am

Title: Reducing resistors in a loop filter of a type II PLL to hasten locking
Post by Hercules Poirot on Aug 8^th, 2017, 8:51am

I came across this scheme whereby during the initial locking phase of a type-II PLL, resistor in the loop filter is shorted out. When the frequency is close enough [probably detected through a counter based frequency detector], the shorts are removed.
What guarantees that the loop will actually lock, when it might have been unstable to begin with?