TLC8044 Datasheet, PDF (1/32 Pages) Texas Instruments – 12-BIT ANALOG-TO-DIGITAL INTERFACE FOR CHARGE-COUPLED DEVICE IMAGE SENSORS FOR SCANNERS

TLC8044
12-BIT ANALOG-TO-DIGITAL INTERFACE FOR
CHARGE-COUPLED DEVICE IMAGE SENSORS FOR SCANNERS
SLAS128 – JUNE 1997
D Color or Gray Scale Operation
D Signals Processed in the Digital Domain
D Differential RGB Input Multiplexer
D Three 8-bit DACs for CCD Offset Level
Shifting With Bipolar Correction Range
D Two Sampling Modes:
– DAC Referenced
– Correlated Double Sampling (CDS)
D 12-Bit ADC with 6 MSPS Operation
D Digital dc Restoration
D Pixel-By-Pixel Offset and Shading (Gain)
Compensation
D Global Gain Adjust for Each Color
(Channel)
D Compatible with 600 dpi CCD Image
Sensors
D Global Offset Adjust for Each Color
(Channel)
D Output Word Length Programmable to 8,
10, 12, or 16 Bits
D Programmable Threshold Detector for Each
Color (Channel)
D Dual Internal Default Registers for
Even/Odd Pixel Offset Correction
D 68-Terminal PLCC Package
applications
D Handy Scanners
D Flatbed Scanners
description
The TLC8044 is a 12-bit analog-to-digital interface subsystem for charge-coupled device (CCD) image sensors
and scanners. An input multiplexer allows color operation with a single on-chip 12-bit ADC. The TLC8044 uses
DSP circuits to correct for nonideal CCD image sensor and scanning system characteristics. Cost effective gray
scale operation is obtained using a single multiplexer input. The TLC8044 three-channel input multiplexer and
sampling function has two basic modes of operation: normal sampling and correlated double sampling. The
internal sample and hold allows all three channels to be sampled simultaneously in color operation. Three DACs
(8 bits + sign) are provided to allow bipolar adjustment of the dc level of the signal at the ADC input. Digital dc
restoration is provided following the ADC. Variations in offset and luminance across a scan are dynamically
corrected on a pixel-by-pixel basis, using calibration data provided by an external data store. Provisions are
made for global adjustments of gain, contrast and color balance, and offset for brightness. The output word
length can be programmed to 8, 10, 12, or 16 bits, and a programmable threshold detector is provided for use
during calibration and OCR applications. The TLC8044 is characterized for operation from 0°C to 70°C.
AVAILABLE OPTIONS
PACKAGE
TA
CHIP CARRIER
(FN)
0°C to 70°C
TLC8044FN
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
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Copyright © 1997, Texas Instruments Incorporated
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