Patent · US Expired

CMOS light sensing cell

US7145123B2 · kind B2 · utility

2Cited by
3References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 12, 2004
Grant dateDec 5, 2006
Priority date
Expiry dateAug 19, 2024

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10F39/803
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A light sensing cell comprising output circuitry for generating an output voltage depending on the voltage of a sensing node, the voltage of the sensing node varying as a function of a received light; a reset transistor operable to force the voltage of the sensing node to a reset voltage; a feedback loop including an operational amplifier operable to add through a capacitive voltage divider a correction voltage to the voltage of the sensing node, said correction voltage depending on the output voltage; and preset mean circuitry for, during the operation of the reset transistor and until the amplifier is operated, setting the input of the capacitive voltage divider to a predetermined voltage.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.