Semiconductor circuits for driving current-driven display and display
US7180513B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Apr 23, 2003 |
| Grant date | Feb 20, 2007 |
| Priority date | — |
| Expiry date | Sep 10, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G3/30
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In a semiconductor circuit of a current output type, when display is performed by plural semiconductor circuit in one display panel, luminance unevenness for each block with a different semiconductor circuit occurs due to fluctuation in the semiconductor circuits. In current output stages, current mirror circuits are constituted at both ends of a chip, and a reference current to be a reference of gradation display is supplied from both the ends. Moreover, by increasing a resistance value of a gate line of the current mirror circuit of distributing a current to each output, deviation of a transistor threshold value in the chip was compensated for, and output currents at left and right ends were matched. Moreover, reference currents were made the same by connecting resistors for reference current generation to each other at least between semiconductor circuits connected side by side, and fluctuation of current values across all semiconductor circuits decreased to 1% or less, whereby unevenness which occurred in boundaries of chips could be eliminated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.