Patent · US Expired

Charge pump

US6856182B2 · kind B2 · utility

3Cited by
7References
10Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJul 2, 2001
Grant dateFeb 15, 2005
Priority date
Expiry dateJul 2, 2021

Classification

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

Abstract

The invention concerns a controllable current source comprising an output terminal for current delivery, which is connected via first and second current paths with first and second supply terminals, wherein the current paths each having a supply side on/off-switchable current control device and an output side current adjustment device. According to the invention, when the current control device is switched off, a predetermined adjustment potential, whose value lies between the two supply potentials, is applied to a node between the current control device and the current adjustment device. In this way, the performance characteristics of the current source are improved, in particular, negative injection and disturbances in the output current can be avoided. When the current source is used in a PLL, the jitter behavior at the output of the VCO is significantly improved.

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