C294Psb / C294Pse Board; Electric Circuit - Epson LQ-300 + Service Manual

EPSON LQ-300+
Table 2-14. Main ICs and Functions
Elements Location
E01A17Axx
CPU
• Outside clock 19.66 MHz/
• Various DMA
• A/D converter (3ch)
G/A
• Bit Manipulation Unit (Print Date Conversion)
CPU/ASIC IC3
• I/O control unit
• Input buffer control unit
• CR/PF/CS motor unit
• Head control unit
CGROM_ IC6 CG (Font)
8M / 16Mbit
PROM IC7 • Stores firmware
• CG
1/2/4M bit switching method, SPJ package 40 pin
DRAM IC8
• Various buffer, work area
AT93C46, 1kbit, SOP 8pin
EEPROM IC5
• Stores default values and various parameters
M62030FP, 8 pin
RESET IC IC4
• CPU reset
CR Motor Driver IC9 A3972SB
PF Motor Driver IC10 A3972SB
Serial I/F Transceiver IC2 MAX202
Operating Principles
Function
Inside clock 39.32 MHz
LED output/Reset control report
EEPROM (94C46) report
Energy Saving mode
CS motor detector (option)
Electric Circuit Operating Principles
Table 2-14. Main ICs and Functions
Elements Location
Regulator IC IC11
Economy Drive Circuit IC12

2.3.2 C294PSB / C294PSE Board

LQ-300+ generates power supply by 2 types of power supply boards: C294PSB
(100V) and C294PSE (200V). The table below shows the power supply boards input
voltage specifications.
Table 2-15. Power Supply Boards Input Voltage Specifications
Circuit
C294PSB
C294PSE

2.3.2.1 Electric Circuit

The power supply board supplies two types of power for control circuit and driving
mechanism. The table below shows output voltage and its use.
Table 2-16. Output Voltage and its Use
Output voltage
35 V +5%/ -10%
5 V ± 5%
NOTE: *: Core voltage of CPU and G/A is 3.3V and it is generated by the
regulator IC on the MAIN board form +5VDC.
Revision C
Function
BA033FP
• Generates 3.3V logic voltage
TL594CN
• 95V rated voltage circuit
• Detects over voltage (over 150V) and sends OFF
signal to the power supply boards.
Input voltage Fuse specification
99 - 132VAC ULTSC-2.5A-NI
198 - 264VAC HT 1.25A
Use
Drive
Logic Voltage*
43