Patent · US Expired

Oscillator with capacitor charged and discharged by current proportional to a reference current

US4494088A · kind A · utility

4Cited by
2References
2Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 26, 1982
Grant dateJan 15, 1985
Priority date
Expiry dateJul 26, 2002

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03K3/0231
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A silicon integrated oscillator circuit is connected with a capacitor and produces a highly precise and stable triangular output voltage. Both the charge current and the discharge current are proportional to one reference current. A switching circuit terminates the charge and discharge intervals when the capacitor voltage reaches a level that is equal to intermediate points on first and second resistive-voltage-divider circuits, respectively. This is accomplished by a differential-transistor-pair comparator having the base of one transistor connected to a high voltage one of the reference points and a third transistor, which is connected collector to emitter across the one transistor, having a base connected to a low voltage one of the reference points.

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