Patent · US Expired

Image sensor

US6291810A · kind A · utility

8Cited by
4References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 26, 1999
Grant dateSep 18, 2001
Priority date
Expiry dateApr 26, 2019

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N25/78
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A voltage at an output terminal of a photodiode is reset to a fixed voltage and an output signal of the photodiode and a dummy signal matching a dark output signal is output by a dummy photodiode comprising an identical component as that of the photodiode. The voltage difference between an input side and an output side of an amplifier is made to match the difference between a reset voltage of the photodiode and a reset voltage of a common signal line and a reset voltage of an output terminal to optimize the size of a MOS transistor forming the amplifier. The offset voltage is set to a constant which does not depend on the size of the MOS transistor. The amplifier is formed with CMOS devices and is selectively operated only during an output operation to suppress the current consumption.

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