PI227 Datasheet, PDF (2/10 Pages) AMI SEMICONDUCTOR – 200DPI CIS Sensor

Applications include document scanning, mark readers, gaming and office automation
equipment.
Functional Description
Each of the three modules in the family, PI227/228/229, consist of four major components.
The first of them is the PCB on which the 27 imaging chips, PI3020, are bonded. These
sensor chips, produced by Peripheral Imaging Corporation, are monolithic devices with 64
photo sensing elements. Each of twenty seven chips are complete self contained
scanning chips and have their control circuits integrated in the chips, so that they can be
cascaded to provide 1728 photo-elements module. The PI3020 chips are integrated with
the photo sensors' associated multiplex switches, a digital shift register and chip selection
switch. The chip's shift register sequentially clocks out the integrated image charges from
each sensing elements and passes them through the chip-select switch and out onto the
video line. The chip-select switches are sequentially switched as each of the predecessor
chip completes its scan. These 27 sensors, bonded on a PCB, are grouped into 4 sub-
cascaded sections. Each contiguously cascaded chips section are connected on
separate video lines, accordingly providing four video outputs VOUT1, VOUT2, VOUT3
and VOUT4. Before the signal charges from the four video lines appear at their
respective outputs they are converted to signal voltages by four on-board buffer
amplifiers, one for each of its corresponding video section. The first three sections
VOUT1, VOUT2, and VOUT3 have 7 sensor chips, while the VOUT4 has 6 sensor chips.
Since each sensor chip have 64 pixels, there are a total of 1728 pixels. See Figure 1.
PI227/228/229 Module Block Diagram.
GLED
VLED
LED
LED
LED LED
LED
LED
LED
LED
123
ROD LENSE
PHOTO SENSORS ¹⁷²⁸
SHIFT REGISTER
BUFFER
VIDEO 1 PIXEL 1 TO 448
VIDEO 2 PIXEL 449 TO 896
VIDEO 3 PIXEL 897 TO 1344
VIDEO 4 PIXEL 1345 TO 1728
AMPL 1
AMPL 2
AMPL 3
AMPL 4
VN(-V)
VDD(+5)
GRD
VOUT1
VOUT2
VOUT3
VOUT4
CP SP
GRD
Figure 1. PI227/228/229 Module Block Diagram
(See Table 1 for pin-out designation)
PAGE 2 OF 10 - PI227/228/229, 01-31-04