Polaroid SprintScan SS35, Руководство по ремонту

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Slide Scanner Repair Manual Functional Description
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Table 2-1. Component Functions (Cont'd)
Component Functions
Image Sensor PC Board Provides biasing and clocking for the CCD array. It
also buffers the CCD outputs and multiplexes them
onto a single line.
Video Signal The VSP processes the buffered analog signal. It
Processor (VSP) contains a preamplifier with voltage controlled gain, a
correlated double sample with offset adjustment, and
an output amplifier.
The VSP also contains three individually controlled
sample-and-hold amplifiers and two 3-to-1 multiplexers
which facilitate dark level adjustment and white
balance correction.
Analog-to-Digital Converts the processed analog signal from the VSP
(A/D) Converter into a digital RGB image signal.
Note: 10-bit A/D converter for SS35/SS35 ES, 12-bit
A/D converter for SS35 PLUS.
Primary Correction ASIC Primary correction is performed by this ASIC. It
concentrates on all processing which can be
performed on a single channel of red, green, or blue
data.
It corrects the brightness, contrast, and color balance
of the RGB image data signal from the A/D converter,
using uniformity correction factors (dark level
uniformity, brightness correction, and uniformity gain
correction) stored in its memory and then sends
corrected RGB image data to the color correction
ASIC.
Buffer Separates (buffers) the two processing ASIC's. It is
used to realign the three colors and serve as a
transfer buffer between the synchronous data
generation by the CCD image sensor and the
asynchronous host SCSI data transfer.