Epson LX-300 Service Manual

LX-300 Sarvice Manual
Oparating Principk
2.3.2 Power On Reset Circuit
When the power supply is turned on, the VL goes up to +9 VDC immediately, but reset IC output
(IC A2, Pin 6) is delayed for approximately 80-
1 ma before going up to +9
VDC. The system IC
-.
receives this
Low
level
signal ‘~om the res& IC and resets itself.
VL
+5V
? t
3ESFT IC
SYSTEM IC
R37 * \:2)
(ICI)
v(-.~ ~
R38
4
4
GND OUT 6
&
‘
3
RESET
T
C24
Figure 2-13. Power On Reset Circuit Diagram
2.3.3 Home Position Sensor Circuit
This printer has a connector switch to sense the carriage home position. The system IC receives a
signal (HIGH or LOW) from the HP sensor and remgnize
the carriage home position when the
printer is turned on. The comector switch is closed (LOW) when the carriage is in the home
position and is open (HIGH) when the carnage is out of home position.
SYSTEM IC
(ICI)
SCK
Figure 2-14. Home
+5V
R73
I
HP Sensor
34
R71
Position Sensor Circuit Diagram
Rev.A
2-13

Epson LX-300 Specifications

General

Print Method	9-pin impact dot matrix
Interface	Parallel
Paper Handling	Friction feed, tractor feed
Weight	4.4 kg
Operating Environment	Temperature: 5 - 35°C, Humidity: 10 - 80%