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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.
