Digitally-controlled automatic gain control circuits for CMOS CCD electronic cameras

Author

Cha, You-Jin ; Lee, Jin-Kug ; Park, Jin ; Lee, Seung-Hoon

Author_Institution

Dept. of Electron. Eng., Sogang Univ., Seoul, South Korea

fYear

1999

fDate

6/21/1905 12:00:00 AM

Firstpage

342

Lastpage

345

Abstract

This paper describes automatic gain control circuit (AGC) design techniques for CMOS CCD camera interface systems. The required gain of the proposed AGC is controlled directly by digital bits without conventional extra digital-to-analog converters. The amplifying function of the AGC is divided into three stages for high-speed operation. A capacitor-segment combination technique considerably improves the effective bandwidth of the AGC. The prototype implemented in a 0.5 μm n-well CMOS process shows the 32-dB AGC dynamic range in 1/8-dB steps with 173 mW at 3 V and 25 MHz. A two-stage AGC is proposed to reduce power and chip area further

Keywords

CCD image sensors; CMOS digital integrated circuits; automatic gain control; digital signal processing chips; direct digital control; high-speed integrated circuits; low-power electronics; 0.5 mum; 173 mW; 25 MHz; 3 V; AGC amplifying function; AGC bandwidth; AGC dynamic range; CMOS CCD camera interface systems; CMOS CCD electronic cameras; automatic gain control circuit design techniques; capacitor-segment combination technique; chip area; digitally-controlled AGC circuits; direct digital bit control; high-speed operation; n-well CMOS process; power reduction; two-stage AGC; Automatic control; CMOS digital integrated circuits; CMOS image sensors; CMOS technology; Cameras; Charge coupled devices; Charge-coupled image sensors; Digital control; Digital-analog conversion; Gain control;

fLanguage

English

Publisher

ieee

Conference_Titel

VLSI and CAD, 1999. ICVC '99. 6th International Conference on

Conference_Location

Seoul

Print_ISBN

0-7803-5727-2

Type

conf

DOI

10.1109/ICVC.1999.820926

Filename

820926