Epson TM-L90 series Service Manual page 133

Confidential
Power circuit
The power circuit generates three voltages (+5 V, +24 V and +3.3 V). Each voltage is supplied to
the circuits listed below:
Table F-2 Output voltages and their applications
Voltage Level
+5 V
+24 V
+3.3V
Power Supply On/Off Control
The figure below shows a block diagram of the power supply and on/off control circuit.
AC
The logic circuit operates according to the specifications listed in the table below.
Table F-3 Logic circuit functions
DC IN Dip switch 1-1
IN ON
OFF
OFF
Appendix F-4 Overview of Electric Circuits
Application
• Logic circuit (used mainly for circuits around CPU)
• Print mechanism power supply
• Drawer kick power supply
• Interface circuit board unit power supply
• Logic circuit (used mainly for circuits around memory)
Power
supply
DIP SW
Power switch
Power Switch
OFF
1 sec ON
3 sec ON
Semiconductor switch
Logic circuit
Power off command
TM-L90
DC Out
ON
ON
OFF
DC output
Rev.B