Patent · US Expired

Driving circuit for a microcomputer that enables sleep control using a small-scale timer

US5737588A · kind A · utility

11Cited by
4References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 7, 1995
Grant dateApr 7, 1998
Priority date
Expiry dateJul 7, 2015

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02D10/00
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

For a system which receives a sleep command to terminate the application of machine clock signals to a microprocessor and which clocks control execution time and stabilization time after the return from sleep control and resumes the supply of the machine clock signal, the clocking device for each of the time durations is implemented using a small-scale timing device. Following a sleep command from a microprocessor, sleep control, which terminates the operation of the main oscillator and the machine clock generation circuit that generates the machine clock signal based on the oscillation of the main oscillator, is started. Then, counting the oscillation signal from an RC oscillator used for clocking using an RC timer, the lapse time after starting sleep control is started and if the clocked time reaches a predetermined time, the main oscillator is reactivated. After reactivating the main oscillator, the RC timer is reset so that it begins to count the time thereafter starting from "0" and if the clocked time reaches the time needed for the oscillation of the main oscillator to stabilize, the machine clock generation circuit resumes its operations.

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