Epson Stylus PHOTO 2000P Service Manual page 47

EPSON Stylus PHOTO 2000P
Table 2-20 shows the major ICs on the C304MAIN Board and their
functions.
Table 2-20. Major Element on C304MAIN
IC Location
CPU (C90A11CA) IC20
ASIC (E05B70**) IC8
Slave CPU
IC15
(C90A26CA)
PROM IC2
OPERATING PRINCIPLES
Functions
A 128-pin SQFP package. Operates at
24.0MHz. Power supply voltage is 3.3V.
• Sets the current value for the ASF/Pump
motor.
• Measures the printhead temperature.
• Several interrupting functions
• Outputs the system clock signal.
A 240-pin QFP package. Operates at 48.0MHz/
24.0MHz/28.0MHz. Power supply voltage is
3.3V.
• Controls interfaces.
• Controls specified motors.
• Controls the printhead drive waveform
circuit.
• Transfers serial data to the printhead.
• Controls the ASF/Pump motor
• Receives panel control signals and sensor
signals
• EEPROM
• Controls detection of the signals output
from the encoder.
A 128-pin SQFP package. Operates at
24.0MHz. Power supply voltage is 3.3V.
• Controls the DC motors. (Setting and
controlling the current value for the PF
motor and CR motor)
8/16Mbit
• Stores the firmware or firmware +CG
Electrical Circuit Operating Principles
Table 2-20. Major Element on C304MAIN
IC Location
DRAM IC3
EEPROM
IC6
AT93C56
Reset IC
IC5
RTC9810SA
NOTE: C298MAIN Board is IC25, which is composed of IC20 and IC8.
Revision A
Functions
A 16Mbit DRAM. Power supply voltage is
3.3V.
• Serves as specified buffers and work area
2kbit
• Stores default setting values and specified
parameters.
• Resets the +5V/+24 VDC line circuits.
• Serves as the timer powered by a lithium
battery.
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