Patent · US Expired

Constant current source stabilized semiconductor oscillator

US4208639A · kind A · utility

9Cited by
6References
8Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 16, 1978
Grant dateJun 17, 1980
Priority date
Expiry dateJun 16, 1998

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03L1/00
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A crystal controlled oscillator has a substantially stable frequency in an environment of wide power supply potential changes. A first CMOS device of a pair is coupled to a crystal network and operates as a substantially small signal linear amplifier. A second CMOS device of the pair forms a constant current source for the first device by means of a plurality of diodes coupled in series circuit between two terminals of the second device to produce a substantially constant biasing potential for the second device only when the potential of the power supply exceeds the value of the diode drop potentials. In this manner, the voltage across the oscillator is relatively independent of power supply voltage changes to provide frequency stability over those changes.

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