AMIS-710330 Datasheet, PDF (7/9 Pages) AMI SEMICONDUCTOR – 300dpi CIS Two-Level Digital Output Module

A_AM_MIS_I-7_S10330: 300dpi CIS Two-Level Digital Output Module
Data Sheet
8.3 Adjustments
8.3.1. General Location of Test, Adjustment and Monitor Points
Figure 5: AMIS-710330 PCB Monitor and Test Points
Figure 5 shows the pictorial layout of the controls and the test points. These adjustment potentiometers and the test points are shown
relative to the connector and to the output pads for LED light power. This is a bird’s eye view of the PCB’s backside with the glass
window of the module facing down on the documents.
The test point labeled TV is for the analog image pixels, just as it is produced at the output of the CIS array section and prior to its entry
into the tracking digitizer circuit.
The test point labeled TR is the output of the tracking reference level from the tracking digitizer circuit.
The test point labeled TVD is the digital output from the comparator.
Offset adjust, R4, is a screw driver adjustment potentiometer, which is accessed through the adjustment hole as it viewed in Figure 5.
Gain adjust, R5, is a screw driver adjustment potentiometer, which is accessed through the hole as it is viewed in Figure 5.
8.3.2. There are Only Two Adjustments
These adjustments will be pre-adjusted at the factory, to the specific application of the customer, thus generally will not require
adjustments by the user.
The gain is adjusted by monitoring the test point TV with a scope, adjusting the gain potentiometer, R5, until the analog image pixel
levels are set to approximately a 2.0V peak with the module imaged on the a standard white target, similar to the standard white copy
or typing paper. (The probe should be grounded as close to the CIS module as possible. The ideal method for grounding would be to
place the probe right on the ground input lead, Pin 5, of the I/O connector.)
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