ASYMMETRIC CHARGE PUMP AND PHASE LOCKED LOOPS HAVING THE SAME

摘要

A charge pump includes a current source configured to generate a first current and a switch circuit including an output node and connected to the current source. The switch circuit is configured to be switched to provide one of the first current to the output node or discharge a second current from the output node according to a phase difference between a reference signal and a feedback signal. The switch circuit is further configured to compare a charge supplied to the output node and a charge discharged from the output node and to adjust an inflow time of the first current to the output node or an outflow time of the second current from the output node according to the comparison result.