Patent · US Expired

Programmable multiphase clock divider

US5477181A · kind A · utility

29Cited by
5References
21Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 13, 1994
Grant dateDec 19, 1995
Priority date
Expiry dateOct 13, 2014

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03L7/0991
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A programmable multiphase clock divider for selectively frequency dividing a multiphase input clock to provide a lower-frequency, self-aligned, multiphase output clock includes a counter, combinational logic circuitry, a multiphase signal generator and a multiplexor. With the counter serving as the sole frequency divider element, multiple phase-aligned clock phases are generated which are then programmably multiplexed to provide the desired frequency-divided, self-aligned clock phases. The counter, in response to a preset signal and an input clock phase, generates a multibit count signal, one bit of which forms the first output clock phase. The combinational logic circuitry receives a programming signal for decoding the multibit count signal to generate the counter preset signal and an output control signal. The multiphase signal generator successively latches the first output clock phase with the aforementioned input clock phase and additional input clock phases to generate a number of synchronous, intermediate clock phases. The multiplexor, in response to the output control signal, multiplexes the intermediate clock phases to provide further output clock phases. All of the output…

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