Patent · US Expired

Charge pump circuit for improving switching characteristics and reducing leakage current and phase locked loop having the same

US6586976B2 · kind B2 · utility

25Cited by
4References
8Claims
0Family size

Assignee

Inventor

Key dates

Filing dateSep 5, 2001
Grant dateJul 1, 2003
Priority date
Expiry dateSep 5, 2021

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03L7/0895
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A charge pump circuit capable of improving the matching and switching characteristics, charge current, and discharge current and reducing leakage current and a phase locked loop including the charge pump circuit. In one aspect, the charge pump circuit comprise a first current source for sourcing current to an output terminal of the charge pump circuit in response to first bias voltage, a first switching device which is switched in response to a first control signal and a pull-down device for pulling down the voltage of a connection node of the first switching device between the first current source in response to the first control signal. In another aspect, the charge pump circuit comprises a second current source for sinking current from the output terminal of the charge pump circuit in response to second bias voltage, a second switching device which is switched in response to a second control signal and a pull-up device for pulling up the voltage of a connection node between the second switching device and the second current source in response to the second control signal.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.