Driver for liquid crystal display apparatus with no operational amplifier
US6127997A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 28, 1998 |
| Grant date | Oct 3, 2000 |
| Priority date | — |
| Expiry date | Jul 28, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G2310/0297
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In a driver in a liquid crystal display apparatus for receiving an input voltage and generating an output voltage to drive a data line, first and second MOS transistors of the same conductivity type have a common gate connected to a drain of the first MOS transistor. A source of the second MOS transistor is connected to an output terminal for generating the output voltage. A first switch is connected between an input terminal for receiving the input voltage and a source of the first MOS transistor, a second switch is connected between a first power supply terminal and the drain of the first MOS transistor, a third switch is connected between the first power supply terminal and a drain of the second MOS transistor, and a fourth switch is connected between a second power supply terminal and the output terminal. The first and second switches are operated to bias a voltage at the gate of the second MOS transistor to a voltage shifted from the gradation voltage by a threshold voltage of the first MOS transistor. The third and fourth switches are operated to operate the second MOS transistor as a source follower.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.