Patent · US Expired

Programmable phase shift and duty cycle correction circuit and method

US7138841B1 · kind B1 · utility

70Cited by
12References
25Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 16, 2004
Grant dateNov 21, 2006
Priority date
Expiry dateFeb 1, 2025

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03K2005/00156
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A phase shift and duty cycle correction circuit is disclosed herein as comprising a programmable digital to analog converter (DAC), a storage device (e.g., a capacitor), a charge sub-circuit and dump sub-circuit for charging and discharging the storage device, respectively, a comparator, and a clock driver circuit. A linearly increasing (or ramped) voltage waveform is generated within the storage device by the charging and discharging actions of the charge and dump sub-circuits; a periodic process which is controlled by opposite phases of the input clock. By programming the DAC control input to change the slicing threshold of the ramped waveform, the circuit and method described herein provides a means for programmable phase shifting and duty cycle correction.

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