LM9800 Datasheet | National Semiconductor

LM9800 8-Bit Greyscale/24-Bit Color Linear CCD Sensor Processor September 1997 LM9800 8-Bit Greyscale/24-Bit Color Linear CCD Sensor Processor General Description The LM9800 is a high performance integrated signal processor/digitizer for linear CCD image scanners. The LM9800 performs all the analog processing (correlated double sampling for black level and offset pensation, pixel-by-pixel gain adjust, and 8-bit analog-to-digital conversion) necessary to maximize the performance of a wide range of linear CCD sensors. The LM9800 can be digitally programmed to work with a wide variety of CCDs from different manufacturers. An internal configuration register sets CCD and sampling timing to maximize performance, simplifying the design and manufacturing processes. The LM9800 can be used with sequential or parallel output color CCDs. Coarse gain switching brings weak Blue signals up to Red/Green levels for best performance. For plementary voltage reference see the LM4041. Applications n Color and Greyscale Flatbed and Sheetfed Scanners n General Purpose CCD Imaging Features n 2.5 million pixels/s conversion rate n Implements Correlated Double Sampling for minimum noise and offset error n Pixel-to-pixel gain correction for individual pixels maximizes dynamic range and resolution, even on “weak” pixels n Reference and signal sampling points digitally controlled in 25ns increments for maximum performance n Generates all necessary CCD clock signals n patible with a wide range of linear CCDs n TTL/CMOS input/output patible Key Specifications n Resolution n Pixel Conversion Rate n Supply Voltage n Supply Voltage (Digital I/O) n Power Dissipation 8 Bits 2.5MHz +5V ±5% +3.3V ±10% or +5V ±5% 210 m W (typ) Connection Diagram TRI-STATE® is a registered trademark of National Semiconductor Corporation. MICROWIRE™ is a trademark of National Semiconductor Corporation. © 1997 National Semiconductor Corporation DS012498 DS012498-1 .national. Block...