AD9943/AD9944

Rev. B | Page 18 of 20

APPLICATIONS INFORMATION

The AD9943/AD9944 are complete analog front end (AFE)

products for digital still camera and camcorder applications. As

shown in Figure 12, the CCD image (pixel) data is buffered and

sent to the AD9943/AD9944 analog input through a series input

capacitor. The AD9943/AD9944 perform the dc restoration,

CDS, gain adjustment, black level correction, and analog-to-

digital conversion. The AD9943/AD9944’s digital output data is

then processed by the image processing ASIC. The internal

registers of the AD9943/AD9944—used to control gain, offset

level, and other functions—are programmed by the ASIC or

microprocessor through a 3-wire serial digital interface. A

system timing generator provides the clock signals for both the

CCD and the AFE.

CCD

CCDIN

BUFFER

AD9943/AD9944

REGISTER

DATA

SERIAL

INTERFACE

DIGITAL

OUTPUTS

DIGITAL IMAGE

PROCESSING

ASIC

TIMING

GENERATOR

V-DRIVE

CCD

TIMING

CDS/CLAMP

TIMING

0.1

µF

Figure 16. System Applications Diagram

24

REFB

23

REFT

22

CCDIN

21

AVSS

D0

1

D1

2

D2

3

20

AVDD

19

SHD

18

SHP

17

CLPOB

D3

4

D4

5

D5

6

D6

7

D7

8

DATA

OUTPUTS

10

910

3V

DRIVER

SUPPLY

3V

ANALOG

SUPPLY

3V

ANALOG

SUPPLY

12 13 14 15 16

5

CLOCK

INPUTS

3

SERIAL

INTERFACE

CCDIN

AD9943

(Not to Scale)

TOP VIEW

1.0

µF

1.0

µF

0.1

µF

0.1

µF

0.1

µF

0.1

µF

NC = NO CONNECT

PIN 1

IDENTIFIER

32 31 30 29 28 27 26 25

11

Figure 17. AD9943 Recommended Circuit Configuration for CCD Mode