Patent · US Expired

Clock duty cycle control technique

US6084452A · kind A · utility

63Cited by
10References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 30, 1998
Grant dateJul 4, 2000
Priority date
Expiry dateJun 30, 2018

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03K5/1565
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

An apparatus adjusts the duty cycle of a single-ended clock signal. The single-ended clock signal oscillates between first and second voltages. The apparatus includes an error indication circuit, a duty cycle error measurement circuit and a duty cycle adjuster. The error indication circuit includes a reference circuit and a comparison circuit. The reference circuit is coupled to a first node having the first voltage and a second node having the second voltage to generate a reference signal from the first and second voltages. The reference circuit includes at least one instance of a first electrical characteristic cell. The comparison circuit is coupled to receive a feedback clock signal and to generate a comparison signal therefrom. The comparison circuit includes at least one instance of the first electrical characteristic cell. The duty cycle error measurement circuit is coupled to receive the reference signal and the comparison signal. The duty cycle error measurement circuit rejects the common mode of the reference and comparison signals and passes the differential mode of the reference and comparison signals to generate a duty cycle adjust signal responsive to receiving the re…

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