PI200MC-A4 Datasheet, PDF (2/7 Pages) AMI SEMICONDUCTOR – 200DPI CIS Module

Block Diagram. This configuration allows a stream of sequential video pixels to be read
from its output port, i.e., starting from 1^st pixel located next to the connector end of the
module and continues to and through the last pixel, 1728^th. Each chip contains a
complete control circuitry. Integrated within monolithic chip is a set of multiplex switches,
and a digital shift register to control the chips sequential readout. Additionally, the chips
contain a chip selection switch that is interrogated in a sequence as each predecessor
chip completes its scanning process.
GLED
VLED
LED
LED
LED
LED
LED
LED
LED
LED
12
34
ROD LENS
PHOTO SENSORS
1726
1728
1727
5 ----------------
VIDEO
LINE
BUFFER
SHIFT REGISTER
VIDEO AMPLIFIER
VN(-V)
VDD (+5)
GRD
VOUT
CP
SP
GRD
Figure 1. PI200M-A4 Block Diagram
Figure 2, PI200M-A4's Cross Section, shows a mechanical cross section of the module's
internal structure. Mounted in the module is number of components. These components
function together to provide the module a complete integrated system. The LED light bar
illuminates the documents through the window and reflection from the imaged documents
is pickup and focused by the one-to-one graded indexed micro lens array.
The lens, through the glass window, focuses the scanned images from the document onto
the sensing plane of the sensor chips, which is mounted on the PCB. During the imaging
process, the document is passed across the glass window's surface.
The PCB board not only has the sensor chips mounted on it, but it has an on-board
amplifier, a clock buffer for both the Start Pulse, SP, and the module's master clock, CP,
buffer. This amplifier processes the pixel charges from the image sensor chips and
converts them into voltage signal to produce a sequential stream of video at the output pin
of the PI200M-A4 module.
PAGE 2 OF 7 - PI200M-A4, 01/31/01