... the analog plus comp
a
TM

EXAR Corporation 48720 Kato Road, Fremont, CA 94538 Phone (510)-668-7000, Fax (510)-668-7030

PRELIMINARY
4

RED

GRN

BLU

VDCEXT

VREF+

DB7:0

DVDD

DGND

AVDD

AGND

ADCCLK

CLAMP

SYNCH

PGA
TIMING &
CONTROL LOGIC
AVDD
6-BIT GAIN
REGISTERS
12-BIT
ADC
RL
AGND
DATA
I/O
PORT
BUFFER VRT
VRB
S/H
&
3-1
MUX
8-BIT DAC
12 8
8-BIT OFFSET
REGISTERS
6
8

+

_

AGND
VDCREF
DC/AC
INT/EXT_VDCREF
CIS/CCD
G<5:0>
O<7:0>
R G B
R G B
CLP
CLAMP
Power
Down
Power
Down
VRT
CCD CIS
VBG
Biasing Circuit for CANON
CIS
Figure 2. Simplified Functional Block Diagram of XRD9827 OPERATIONAL PROCEDURE The routine listed below will first calibrate the photo response of the CIS using the XRD9827 by optimize its offset and gain. After calibration, the XRD9827REF can be used to scan any color target to show CIS non-color corrected response. (Color correction is typically done in the digital ASIC.)