XRD9818

www.DataSheet4U.com xr JUNE 2004 XRD9818 REV. 1.0.1 3-CHANNEL 16-BIT LINEAR CCD/CIS SENSOR SIGNAL PROCESSOR GENERAL DESCRIPTION The XRD9818 is a fully integrated, high-performance analog signal processor/digitizer specifically designed for use in 3-channel/2-channel/1-channel CCD/CIS document imaging applications. Each channel of the XRD9818 includes a Correlated Double Sampler (CDS), Offset adjustment, Programmable Gain Amplifier (PGA). After the gain and offset adjustments the analog inputs are sequentially sampled and digitized by a 16-bit A/D converter. The digital output data is available in 8 or 4-bit wide multiplexed format. The analog front-end can be configured for use in CCD or CIS data acquisition applications. The CDS mode of operation supports both line and pixel-clamp modes and can be used to achieve significant reduction in system 1/f noise and CCD reset clock feed-through. Five programmable clamp levels are available in CCD mode to adjust for CCD signal swing and reset pulse size. For CIS mode there are 3 selectable reference options, two internally generated and one external applied reference. Two PGA ranges, programmable through the serial port, help interface the XRD9818 to CCD imagers that have either a 3V or 2V output swings. The range of 1x to 5x is used for 3V inputs and the range of 1.5x to 7.5x is used for 2V inputs. Each channel has an offset range of -180mV to 180mV (1.4mV/step) for fine adjustment and an additional -100mV to 200mV (100mV/step) ...