Patent · US Expired

Pulse stretching and level shifting circuit

US4501974A · kind A · utility

6Cited by
3References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 13, 1982
Grant dateFeb 26, 1985
Priority date
Expiry dateDec 13, 2002

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03K5/04
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A pulse stretching integrated circuit includes an on-chip capacitor. A first transistor means including an input transistor and an emitter follower transistor supplies a charging current to the capacitor so as to charge it to a first voltage when an input signal pulse is in a first logical state. A differential transistor pair has a first input coupled to the emitter follower transistor and to the capacitor and has a second input coupled to a reference voltage for generating a first output when the capacitor voltage is less than the reference voltage and for generating a second output when the capacitive voltage is greater than the reference voltage. An additional transistor is coupled to the capacitor for discharging the capacitor when the input signal pulse is in a second logical state causing the voltage at the first input of the differential pair to fall below the reference voltage.

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