C298Main Board - Epson Stylus COLOR 1160 Service Manual

EPSON Stylus COLOR 860/1160

2.2.2 C298MAIN Board

The logic circuit of the C298MAIN is composed of the following:
n
Logic line (CPU, ASIC, DRAM, EEPROM, and so on)
n
Various motor control/driver circuits (CR motor, PF motor, and ASF/
Pump motor)
n
Head control/driver circuits
n
Interface control (parallel I/F, USB I/F)
n
Sensor circuits
n
Timer circuits
n
Reset circuits
This main board is mainly different form other models in the following two
points.
o
Use of the 3.3V chips in the logic circuit
The 3.3 V regulator (IC9) on the C298MAIN produces 3.3 V by pressuring
down the 5.5 VDC, also generated on this board, to drive several chips.
See the table below that separately shows the chips driven by the +5V and
+3V.
Table 2-10. 3.3V Drive Chips & 5.5V Drive Chips
+5V
Sensors
I/F Circuit
PNL Board
Slave CPU
o
Use of the slave CPU
Since the CR motor and PF motor of this printer are DC motors, the slave
CPU is attached on the main board in addition to the CPU and ASIC. This
slave CPU, serving to control the DC motors only, reduces duty of the CPU
and ASIC for faster data processing.
See Figure 2-16 for the C298MAIN board block diagram.
Operating Principles
3.3V
CPU
ASIC
P-ROM
D-RAM
Electrical Circuit Operating Principles
CR Encoder senser
CN8 HD FFC
Head
CN9 HD FFC
Batt1
D-RAM 16M
P-ROM 16M
(IC3) Timer &
(IC2)
Address
Reset IC
Data
EEPROM
C90A11CA
E05B70OD
CPU (IC20)
ASIC (IC8)
Address
Data
CN5
IC7
E0BA13KA
CN3
CN12
USB
IC21
PDIUSBF11A
PF Encoder Sensor
Figure 2-16. Block Diagram for the C298MAIN Board
Revision C
CR Motor
CR1
PF Motor
Q3&Q4
ASF/Pump Motor
Common
(IC5)
CN14
Driver
(IC10 or
CN7
IC11) CN13
(IC6)
Motor Motor
Motor
Driver Driver Driver
(IC18) (IC19) (IC12)
C90A120A
Slave CPU (IC15)
IC4
CN1 Parallel
74VHC1612B4
CN11
CN 6
C298 PNL (for SC860)
C303 PNL (for SC1100)
ASF Sensor
PE Sensor
43