REV. 0

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a

AD9845A

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., 2001

Complete 12-Bit 30 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

12

CDS

VGA

CLP

BUF

2:1

MUX

CLP

AD9845A

CONTROL

REGISTERS

CLP

ADC

4dB

6dB

COLOR

STEERING

HD

VD

PxGA

6

FEATURES

30 MSPS Correlated Double Sampler (CDS)

4 dB

6 dB 6-Bit Pixel Gain Amplifier (

2 dB to 36 dB 10-Bit Variable Gain Amplifier (VGA)

Low Noise Clamp Circuits

Analog Preblanking Function

12-Bit 30 MSPS A/D Converter

Auxiliary Inputs with VGA and Input Clamp

3-Wire Serial Digital Interface

3 V Single Supply Operation

Low Power: 140 mW @ 3 V Supply

48-Lead LQFP Package

APPLICATIONS

Digital Still Cameras

Digital Video Camcorders

Industrial Imaging

PRODUCT DESCRIPTION

The AD9845A is a complete analog signal processor for CCD

applications. It features a 30 MHz single-channel architecture

designed to sample and condition the outputs of interlaced and

progressive scan area CCD arrays. The AD9845A’s signal chain

consists of an input clamp, correlated double sampler (CDS),

Pixel Gain Amplifier (PxGA), digitally controlled variable gain

amplifier (VGA), black level clamp, and a 12-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

adjustment, black level adjustment, input configuration, and

power-down modes.

The AD9845A operates from a single 3 V power supply, typi-

cally dissipates 140 mW, and is packaged in a 48-lead LQFP.

PxGA is a registered trademark of Analog Devices, Inc.