Control Circuit; Control Circuit Operation - Epson TM-FX2180 Service Manual

EPSON FX-2180 Service Manual
The figure below shows the power supply circuit block diagram.
primary circuit
AC input
full-wave
smoothing
filter circuit
rectification
circuit
circuit
C244 PSH only
voltage
doubler
rectification
automatic
switching
circuit
Figure 2-2. Power Supply Circuit Block Diagram

2.1.3 Control Circuit

The printer's control circuit consists of the C244 MAIN control board and
the control panel board.
2.1.3.1

Control Circuit Operation

The control circuit includes a TMP96C141BF CPU that runs at 17.20 MHz,
an E05B50** gate array, a 2 Mbit PROM (or 2 Mbit / 4 Mbit flash ROM), a 1
Mbit / 4 Mbit PS-RAM (or SRAM), a serial (or parallel) EEPROM, and other
circuits. The control circuit controls all the printer's components. Figure 2-3
shows the control circuit block diagram.
secondary circuit
+5 V switching
regulator
+5 V constant voltage
control circuit
+5 V over-current
protection circuit
switching smoothing
circuit
circuit
+35 V line
overload
photo-
detector circuit
coupler
+35 V line
constant voltage
control circuit
photo-
+35 V line
coupler
over-voltage
protection circuit
+5 V line
over-voltage
protection circuit
+35 V line
over-current
protection circuit
+5 VDC
type B I/F
parallel I/F
+35 VDC
control panel
buttons & LEDs
CPU
port 20
Operate button
PSC
PWDN
Operate
(power) button
power supply
board
Chapter 2 Operating Principles
PS-RAM
IC3
IC5 EPROM
or SRAM
IC1
gate array
E05B50**
IC8
serial
EEPROM
IC15
reset IC
5 V
GL
35 V
GP
IC12
IC9
PF driver CR driver
SLA7024M
UDN2917EB
Figure 2-3. Control Circuit Block Diagram
Q2-Q19
print head
temperature
print head
sensor
driver
+35 V voltage
sensor
rear PE
sensor
front PE
IC2
sensor
CPU
TMP96C141BF
TOP
sensor
home
position
sensor
paper
release
lever sensor
platen gap
lever
sensor
CSF
CSF driver
sensor
: data bus
: address bus
2-3