Patent · US Expired

Delay circuit of clock synchronization device using delay cells having wide delay range

US6686788B2 · kind B2 · utility

11Cited by
14References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 6, 2002
Grant dateFeb 3, 2004
Priority date
Expiry dateMay 6, 2022

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03L7/0995
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A delay circuit of a clock synchronization device that includes an operational amplifier for setting the level of a current control voltage according to a voltage difference between a regulation voltage and a reference voltage. A number of unit delay cells connected in series are included, each having a delay time set according to a resistance control voltage and the current control voltage. Also, a variable resistance unit is included having a resistance value adjusted according to the resistance control voltage, where the variable resistance unit includes a cross coupled adjustment device that outputs signals to a next unit delay cell. The delay cells are controlled by using the operational amplifier and a replica cell to have a wide delay range. As a result, the working range can be set wide, jitters may be reduced and the chip size may also be reduced.

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