摘要 |
A loop circuit such as a delay lock loop or a phase lock loop includes circuitry for changing the strength of the lock after lock has been achieved. Before lock is achieved, the strength of the charge pump circuitry that controls the charge in the low-pass filter in the loop may be relatively weak. After lock has been achieved, the strength of the charge pump circuit may be increased so that the circuit can maintain its locked condition in a noisy environment.
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