Image display device using a scanning and hold display mode for power saving purposes
US7126595B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 8, 2001 |
| Grant date | Oct 24, 2006 |
| Priority date | — |
| Expiry date | Apr 20, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G2330/023
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Adapting to load currents which differ by more than 100 times between a scanning mode and a hold mode, a frequency of pump operation is decided according to the maximum value of the load currents, and circuit elements of a power supply, for example, such as capacitance of a capacitor for pump operation or a smoothing capacitor, element configurations of switching elements, or capacitance or resistance value of a CR oscillator are set based on this frequency, so that a load current detector lowers the frequency of the pump operation under light load to reduce a self-loss of power in the power supply. This realizes a charge-pump power supply which is installed in a liquid crystal display device of a terminal device of a portable phone, with reduced power consumption under light load and a longer standby time.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.