Patent · US Active

Phase locked loop with simultaneous locking to low and high frequency clocks

US8907706B2 · kind B2 · utility

2Cited by
6References
18Claims
0Family size

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Inventors

Key dates

Filing dateApr 28, 2014
Grant dateDec 9, 2014
Priority date
Expiry dateApr 28, 2034

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03L7/101
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A phase-locked loop to is simultaneously synchronized to high and low frequency clocks by (i) locking an output of the phase-locked loop to a high-frequency reference clock, (ii) measuring at a high rate a first phase difference between the high-frequency reference clock and the output of the phase-locked loop, (iii) measuring at a high rate a second phase difference between a low-frequency reference clock and the output of the phase-locked loop; (iv) computing at a low rate from said first and second phase differences a third phase difference between the high-frequency and low frequency clocks; (v) combining at a low rate said third phase difference with said second phase-difference to obtain a total phase difference; and (vi) adjusting the output of the phase-locked loop at a low rate to reduce the obtained total phase difference.

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