Control Circuit Overview - Epson Perfection 1250 Service Manual

EPSON Perfection 1250/1250 PHOTO

2.2 Control Circuit Overview

The scanner uses a single-chip, 16-bit bus CPU (IC16) which has a
transmission frequency of 20 MHz. Input image signal correction, image
processing and CCD sensor control are controlled by the ASIC (IC10). Table
2-1 describes each of the main ICs function.
Table 2-1. Description of Main ICs
IC Location
T224162B-35J IC1
NM24C02M8X IC2
ILX555K IC4
LM9833 IC5
NJM78M120LA-TE1 IC7
PC1 RPI-576
SW1.2.3.4 CARBON SWITCH Push Switch
LED1 SML-020MLT
Function
DRAM 256 x 16bit
Reset IC
CCD
ASIC : Manages the following
• CCD control
• Image processing
• USB 1.1 Interface
• Stepping motor control
• Input image signal correction
• General-purpose I/O
• Programmable frequency divider
• Buffer control
Regulator
CR home position sensor
LED
Ready : Green
Error : Red
Technical Overview
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