Patent · US Expired

Method for reducing power consumption in a portable electronic device with a liquid crystal display screen

US5890799A · kind A · utility

66Cited by
16References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 10, 1997
Grant dateApr 6, 1999
Priority date
Expiry dateNov 10, 2017

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F1/3218
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A method and apparatus for reducing power consumption in a portable electronic device (100) with an LCD screen (104) and operating with a CPU (114) switchable between a high power mode and a low power mode. When input commences on a surface of the LCD screen (104), an interrupt signaler (108) generates a first interrupt signal to an interrupt controller (112). Upon receiving the first interrupt signal, the interrupt controller (112) switches the CPU (114) from the low power mode to the high power mode, turning on at least one detection panel (106) coupled to the LCD screen (104) and to an ADC (110). When input ceases on the surface, the interrupt signaler (108) generates a second interrupt signal to switch the CPU (114) from the high power mode to the low power mode, turning off the at least one detection panel (106) and the ADC (110).

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