Patent · US Active

Analog duty cycle correction loop for clocks

US7898309B1 · kind B1 · utility

8Cited by
3References
14Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMay 14, 2009
Grant dateMar 1, 2011
Priority date
Expiry dateMay 14, 2029

Classification

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

Abstract

Providing duty cycle correction can include determining whether a clock signal has a duty cycle greater than 50% based on averaging the clock signal and comparing that averaged clock signal to ½ VDD. When the duty cycle is greater than 50%, the clock signal can be selected. When the duty cycle is less than 50%, the inverted clock signal can be selected. Thus, a duty cycle corrected clock signal can be generated based on the clock signal or the inverted clock signal. Notably, a duty cycle control signal can be adjusted based on comparisons of an averaged, duty cycle corrected clock signal and predetermined low/high voltage ranges. Components performing comparing functions can be strobed based on a count performed on the clock signal.

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