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Analog Devices AD9843A User Manual

Ad9843a, Complete 10-bit 20 msps ccd signal processor

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Information furnished by Analog Devices is believed to be accurate and
reliable. However, no responsibility is assumed by Analog Devices for its
use, nor for any infringements of patents or other rights of third parties
which may result from its use. No license is granted by implication or
otherwise under any patent or patent rights of Analog Devices.

a

AD9843A

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781/329-4700

World Wide Web Site: http://www.analog.com

Fax: 781/326-8703

© Analog Devices, Inc., 2000

Complete 10-Bit 20 MSPS

CCD Signal Processor

FUNCTIONAL BLOCK DIAGRAM

DATACLK

SHD

SHP

BANDGAP

REFERENCE

2:1

MUX

DOUT

AUX2IN

CLPDM

CCDIN

OFFSET

DAC

PBLK

AUX1IN

VRT

VRB

INTERNAL

TIMING

INTERNAL

BIAS

2dB~36dB

AVDD

DVDD

DVSS

AVSS

DRVDD

DRVSS

10

8

CML

DIGITAL

INTERFACE

SDATA

SCK

SL

CLPOB

10

CDS

VGA

CLP

BUF

2:1

MUX

CLP

AD9843A

4dB

؎6dB

INTERNAL

REGISTERS

CLP

10-BIT

ADC

6

FEATURES
20 MSPS Correlated Double Sampler (CDS)
4 dB

؎ 6 dB Variable CDS Gain with 6-Bit Resolution

2 dB to 36 dB 10-Bit Variable Gain Amplifier (VGA)
Low Noise Clamp Circuits
Analog Preblanking Function
10-Bit 20 MSPS A/D Converter
Auxiliary Inputs with VGA and Input Clamp
3-Wire Serial Digital Interface
3 V Single Supply Operation
Low Power: 65 mW @ 2.7 V Supply
48-Lead LQFP Package

APPLICATIONS
Digital Still Cameras
Digital Video Camcorders
PC Cameras

PRODUCT DESCRIPTION
The AD9843A is a complete analog signal processor for CCD
applications. It features a 20 MHz single-channel architecture
designed to sample and condition the outputs of interlaced and
progressive scan area CCD arrays. The AD9843A’s signal chain
consists of an input clamp, correlated double sampler (CDS),
digitally controlled variable gain amplifier (VGA), black level
clamp, and 10-bit A/D converter. Additional input modes are
provided for processing analog video signals.

The internal registers are programmed through a 3-wire serial
digital interface. Programmable features include gain adjust-
ment, black level adjustment, input configuration, and power-
down modes.

The AD9843A operates from a single 3 V power supply, typi-
cally dissipates 78 mW, and is packaged in a 48-lead LQFP.