EXAR Corporation, 48720 Kato Road, Fremont, CA 94538 • (510) 668-7000 • FAX (510) 668-7017 • www.exar.com
XRD9827
12-Bit Linear CIS/CCD Sensor
Signal Processor with Serial Control
December 2000-2
FEATURES
· 12-Bit Resolution, No Missing Codes
· One-channel 6MSPS Pixel Rate
· Triple-channel 2MSPS Pixel Rate
· 6-Bit Programmable Gain Amplifier
· 8-Bit Programmable Offset Adjustment
· CIS or CCD Compatibility
· Internal Clamp for CIS or CCD AC Coupled
Configurations
· 3.0V or 5V Operation & I/O Compatibility
· Serial Load Control Registers
· Low Power CMOS: 200mW-typ
· Low Cost 20-Lead Packages
· USB Compliant
APPLICATIONS
· Color and Grayscale Flatbed Scanners
· Color and Grayscale Sheetfed Scanners
· Multifunction Peripherals
· Digital Color Copiers
· General Purpose CIS or CCD Imaging
· Low Cost Data Acquisition
· Simple and Direct Interface to Canon 600 DPI
Sensors
ORDERING INFORMATION
Package Type Temperature Range Part Number
20-Lead SOIC 0°C to +70°C XRD9827ACD
20-Lead SSOP 0°C to +70°C XRD9827ACU
GENERAL DESCRIPTION
The XRD9827 is a complete linear CIS or CCD sensor
signal processor on a single monolithic chip. The
XRD9827 includes a high speed 12-Bit resolution ADC,
a 6-Bit Programmable Gain Amplifier with gain adjust-
ment of 1 to 10, and 8-Bit programmable input referred
offset calibration range of 800mV.
In the CCD configuration the input signal is AC coupled
with an external capacitor. An internal clamp sets the
black level. In the CIS configuration, the clamp switch
can be disabled and the CIS output signal is DC coupled
from the CIS sensor to the XRD9827. The CIS signal
is level shifted to VRB in order to use the full range of
the ADC. In the CIS configuration the input can also be
AC coupled similar to the CCD configuration. This
enables CIS signals with large black levels to be
internally clamped to a DC reference equal to the black
level. The DC reference is internally subtracted from
the input signal.
The CIS configuration can also be used in other appli-
cations that do not require CDS function, such as low
cost data acquisition.
Rev. 3.00
