High voltage reset method for increasing the dynamic range of a CMOS image sensor
US6864920B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 24, 2001 |
| Grant date | Mar 8, 2005 |
| Priority date | — |
| Expiry date | Jun 25, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N25/779
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A circuit and method for increasing the dynamic range of CMOS image sensors designed with a thin gate oxide layer. The circuit includes a high voltage supply circuit and a high voltage level shifter circuit. The high voltage supply circuit is configured to supply a voltage to the shifter circuit. The voltage has a voltage level higher than the maximum supply voltage of the associated fabrication process. The shifter circuit is configured to output a high reset signal based on a reset signal generated to reset a pixel circuit of a pixel array. Instead of the reset signal, the high reset signal is coupled to a gate of the reset transistor in the pixel circuit. The high reset signal allows the reset transistor to maintain a gate to source potential less than the maximum supply voltage even when the high reset signal is greater than the maximum supply voltage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.