CMOS image sensor with active reset and 4-transistor pixels
US7800676B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | May 24, 2007 |
| Grant date | Sep 21, 2010 |
| Priority date | — |
| Expiry date | Jul 7, 2028 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N25/77
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A CMOS image sensor implementing a low noise active reset operation uses control circuitry outside a pixel sensor array and transistors in a pixel sensor as parts of an amplifier that charges a photodiode node. In one configuration, a reference transistor in the control circuit controls a current mirrored to a column line, and each pixel sensor in the corresponding column contains a transistor that acts as half of a differential pair when the row containing the pixel sensor is selected. A 4-transistor pixel sensor can be implemented using only NMOS transistors with PMOS transistors in the control circuitry used to complete an amplifier circuit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.