EPSON Perfection 1240U
Revision A
Operating Principles
Control Circuit
20
2.2 Control Circuit
The CPU (IC12) of this scanner is a one-tip 16-bit bus CPU operating at
20MHz. ASIC (IC10) manages input signal correction, image processing, and
controlling the CCD sensor board and USB interface. The power supply control
uses a DC/DC converter to generate 5 V and 12 V signals from the 24 V DC
input. Table 2-1 shows the major IC functions.
Figure 2-5. Control Circuit Diagram
Table 2-1. Major ICs
IC
Location
Functions
M37920
IC12
CPU
24-bit Address Bus
16-bit Data Bus
MB81F6416420-102
IC13
SDRAM 4M x 16bit
IS61C6416
IC17
SRAM 64k x 16bit
E02A32SA
IC10
ASIC: Manages the following:
• Input image signal correction
• CCD control
• Line control
• Image processing
• Memory control
• Data in/output control
A3957SLBTR
IC4,5
CR motor driver IC
M51953A
IC11
Reset IC
M27C1001-10F1
IC9
PROM 4M x 8bit
IS61C256AH
IC16
SRAM 32k x 8bit
GP1S58V
PC1
CR home position sensor
NJM2360
IC1,2
DC/DC Converter
AD9822
IC19
8bit A/D Converter
E02A35BA
IC14
USB interface control
SSR20.00BA
CR1
Clock 20MHz
NJM78M12
IC8
Regulator (12VDC)
CCD Board
Lamp
&
Inverter Board
Image Data
(R/G/B)
8-bit
Data
E02A34EB (IC10)
SRAM
(IC17)
SDRAM
(IC13)
(IC16)
(IC9)
(PC1)
CPU (IC12)
CLK(CR1)
CR Motor
Driver
(IC4,5)
CR
Motor
PROM
USB
Controller
(IC14)
USB
Reset IC
(IC11)
SRAM
H.P.
A/D
Converter
(IC19)
+24VDC
Regulator
(IC8)
+12VDC
+24VDC
DC/DC
Converter
(IC1,2)
+5VDC
Address Bus
Data Bus
Option
Sensor
Содержание Series Perfection 1240U Series
Страница 7: ...C H A P T E R 1 PRODUCT DESCRIPTION ...
Страница 17: ...C H A P T E R 2 OPERATINGPRINCIPLES ...
Страница 21: ...C H A P T E R 3 TROUBLESHOOTING ...
Страница 25: ...C H A P T E R 4 ASSEMBLYANDDISASSEMBLY ...
Страница 43: ...C H A P T E R 5 ADJUSTMENT ...
Страница 45: ...C H A P T E R 6 MAINTENANCE ...
Страница 47: ...C H A P T E R 7 APPENDIX ...
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