Departmental Papers (ESE)

Document Type

Journal Article

Date of this Version

11-1-2007

Comments

Copyright 2007 IEEE. Reprinted from IEEE Journal on Solid State Circuits, Volume 42, Issue 11, November 2007, pages 2482-2491.

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Abstract

A current mode CMOS active pixel sensor (APS) providing linear light-to-current conversion with inherently low fixed pattern noise (FPN) is presented. The pixel features adjustable-gain current output using a pMOS readout transistor in the linear region of operation. This paper discusses the pixel’s design and operation, and presents an analysis of the pixel’s temporal noise and FPN. Results for zero and first-order pixel mismatch are presented. The pixel was implemented in a both a 3.3 V 0.35 µm and a 1.8 V 0.18 µm CMOS process. The 0.35 µm process pixel had an uncorrected FPN of 1.4%/0.7% with/without column readout mismatch. The 0.18 µm process pixel had 0.4% FPN after delta-reset sampling (DRS). The pixel size in both processes was 10 X 10 µm2, with fill factors of 26% and 66%, respectively.

Keywords

CMOS analog integrated circuits, image sensors

 

Date Posted: 04 December 2007

This document has been peer reviewed.