LM9833 48-Bit Color, 1200dpi USB Image Scanner Literature Number: SNAS566 LM9833 48-Bit Color, 1200dpi USB Image Scanner
General Description Features The LM9833 is a complete USB image scanner system on a single IC. The LM9833 provides all the functions (image sensor
control, illumination control, analog front end, pixel processing
function image data buffer/DRAM controller, microstepping
motor controller, and USB interface) necessary to create a high
performance color scanner. The LM9833 scans images in 48 bit
color/16 bit gray, and has output data formats for 48 and 24bit
color/16 and 8 bit gray. The LM9833 supports sensors with pixel
counts of up to 16384 pixels x 3 colors (1200 dpi x 13.6 inches). 16 bit ADC digitizes at up to 6Mpixels/s (2M RGB pixels/sec). Digital Pixel Processing provides 1200, 800, 600, 400, 300,
200, 150, and 100dpi horizontal resolution from a 1200dpi
sensor and 600, 400, 300, 200, 150, 100, 75, and 50dpi
horizontal resolution from a 600dpi sensor. Provides 50-2400dpi vertical resolution in 1 dpi increments. Pixel rate error correction for gain (shading) and offset errors. Supports 4 or 16Mbit external DRAMs. Multiple CCD clocking rates allows matching of CCD clock to
scan resolution and pixel depth for maximum scan speed. Stepper motor control tightly coupled with image data buffer
management to maximize data transfer efficiency. PWM stepper motor current control allows microstepping for
the price of fullstepping. USB interface for Plug and Play operation on USB-equipped
computers. Serial EEPROM option for custom Vendor and Product IDs. Support for USB bus-powered operation. Pixel depths of 1, 2, or 4 bits are packed into bytes for faster
scans of line art and low pixel depth images. Supports 3 channel CCDs and 1 channel CIS sensors. 3 (R, G, and B) 12-bit, user-programmable gamma correction
tables. Compatible with a wide range of color linear CCDs and
Contact Image Sensors (CIS). Operates with 48MHz external crystal. Internal bandgap voltage reference. 100 pin TQFP package The LM9833’s low operating and suspend mode supply currents
allow design of USB bus-powered scanners. The only additional
active components required are an external 4Mbit or 16Mbit
DRAM for data buffering and power transistors for the stepper
motor. Applications Color Flatbed Document Scanners …
