C612 Main Board - Epson Stylus CX3700 Service Manual

EPSON Stylus CX3700/CX3800/CX3805/CX3810/DX3800/DX3850
2.4.2 C612 Main Board
The logic circuit of the C612 Main Board is composed of the follows;
Logic line (CPU-ASIC 2 in 1, SDRAM, P-ROM and so on)
Motor control/drive circuit (CR Motor, PF Motor, Scanner Motor)
Head control/drive circuit
USB Interface control circuit
Sensor circuit
Combination circuit (RTC circuit, Reset circuit, EEPROM circuit)
The printer mechanism is controlled by the above circuits. Following explains the
major characteristics of this Main Board.
Lithium battery is not mounted
Unlike the previous printer (Stylus COLOR 680), the Lithium battery is not
mounted on the Main Board.
Adoption of 3.3V/1.5V drive logic circuit components
The 5V formed by the Combination Motor Driver (IC9) of C612 Main Board is
stepped down to 3.3V by the Regulator (IC10), and it is then used as drive voltage
for many elements. In addition, when SPC shifts to low power mode, the 3.3V that
was stepped down by the Regulator (IC10) is stepped down to 1.5V by the
Combination Motor Driver (IC9) and elements that had been driven by 3.3V are
driven by 1.5V for suppression of power consumption.
Table 2-8. Drive Components
5VDC
• RTC (IC7) • Flash ROM (IC5)
• SDRAM (IC6)
OPERATING PRINCIPLES
3.3 VDC 3.3/1.5VDC
• CPU-ASIC (IC8)
• Motor driver (IC9)
• Common driver (IC11)
Electrical Circuit Operating Principles
2.4.2.1 Main Elements
Table 2-9 (p.54) shows the function of the each main elements on C571/577 Main
Board.
Table 2-9. Main Elements
IC Location
8Mbit
Flash ROM IC5
• Firmware storage
SDRAM IC6 Bus= 16 bit, 64Mbit DRAM
• EEPROM
Default settings, backup for all parameters
RTC IC7
• Reset function
• Timer function
CPU mounted on the MAIN board is driven by clock
CPU-ASIC IC8 frequency 48 MHz, 96MHz and controls the printer and
scanner.
• CR/PF/Scanner motor drive IC
Motor Driver IC9 • Dropping 42V line to 5V
• Dropping 5V line to 3.3V
Regulator IC10 Dropping 3.3 V line to 1.5 V
Head drive control HIC
Common Driver IC11
• Generates head common voltage.
Revision A
Function
54