Liquid crystal drive device
US7342562B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 23, 2004 |
| Grant date | Mar 11, 2008 |
| Priority date | — |
| Expiry date | Jan 7, 2026 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G2330/021
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
By implementing reduction in power of common electrode voltages applied from a power source of a liquid crystal drive device to common electrode interconnects of a liquid crystal display panel, respectively, reduction in power consumption of the liquid crystal display panel as a whole is attained.A VCOM operation waveform in a charging process from a second voltage VCOML to a first voltage VCOMH shows that a charging current Icha represents the sum of a charging current from VCOML to a reference voltage VCI, Icha1=Cp (VCI−VCOML)/Δt, and a charging current from the reference voltage VCI to the first voltage VCOMH, Icha2=Cp (VCOMH−VCI)/Δt. Accordingly, power consumed by Icha1 is the reference voltage VCI×Icha1, and power consumed by Icha2 is VCI×Icha2×2. Meanwhile, a discharging current at a time of discharging from the first voltage VCOMH to the second voltage VCOML is the sum of a discharging current from the first voltage VCOMH to the ground potential GND, Idis1=Cp (VCOMH−GND)/Δt, and a discharging current from the ground potential GND to the second voltage VCOML, Idis2=Cp (GND−VCOML)/Δt. Now, if converted in terms of power consumed at the reference voltage VCI, since Idis1 repres…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.