Patent · US Expired

Method and circuitry for equalizing the differing delays of semiconductor chips

US4287437A · kind A · utility

6Cited by
5References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 29, 1979
Grant dateSep 1, 1981
Priority date
Expiry dateNov 29, 1999

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03K2005/00163
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

For equalizing the signal delay times of semiconductor chips a digital control circuit is provided on each chip. By altering the supply voltage, the digital control circuit influences the signal delay times. The digital control circuit comprises a comparator circuit where the signal delay of a clock pulse is compared in a chain of inverters with the very precisely defined clock interval. Depending on the result of the comparison, the count of an up-down counter is incremented or decremented by one. The resulting count is decoded and converted into a corresponding voltage for operating the circuits of the semiconductor chip. Subsequently, the above described steps are repeated until the difference .DELTA.t between the arrival of a clock pulse delayed by the chain, and the following undelayed clock pulse approaches zero.

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