Patent · US Expired

Real time clock

US5740129A · kind A · utility

19Cited by
2References
17Claims
0Family size

Assignee

Inventor

Key dates

Filing dateFeb 6, 1996
Grant dateApr 14, 1998
Priority date
Expiry dateFeb 6, 2016

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02D30/70
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A real time clock is arranged to generate output signals indicative of time of day. An oscillating device (101) produces a first clocking signal which is adjusted in response to a calibration value to produce an output clocking signal. A processor (102) re-calculates the calibration value in response to external clocking signals received from a cellular base station for mobile telephones. The clock may be provided within a mobile telephone and the oscillating device may also be used to provide sleep clock signals allowing a high frequency system clock to be de-activated for periods while the telephone is in a stand-by condition.

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