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3. Power Supply Check
1.
The power supply unit outputs the following four kinds of voltages.
2.
The voltages output from the power supply unit can be checked with the LEDs on the PWB of
the unit.
1) Vth:
The LED lights only during printing.
2) 24 V:
The LED lights when the ink cassette and film cassette are present and the door is closed.
3) 5 V:
The LED lights when the power switch is ON.
3.
The voltages generated in the MAIN PWB are output to their target PWBs. For details, see the
overall block diagram.
5V
12V
24V
Vth
H.T.Protector
—
—
—
MAIN
MAIN
MAIN
MAIN
DRIVE
DRIVE
DRIVE
—
FRONT
FRONT
—
—
Source Device
Power Supply Unit
Power Supply Unit
Power Supply Unit
Power Supply Unit
Target PWB
Usage
5V Logic IC
Analog IC (Amp, Comp etc)
Actuator
Thermal Head
5V
TOP
24V Vth
3.3V
1.9V
2.5V
5VREF
3.3VREF
CPU
CPU
CPU
—
CPU
USB IF
—
—
—
—
MAIN
—
—
MAIN
—
—
—
—
DRIVE
—
—
—
—
—
—
Regulator IC (5V to 3.3V)
Regulator IC (5V to 1.9V)
Regulator IC (5V to 2.5V)
Shunt Regulator (12V to 5V)
3.3V LV IC (CPU, Memory etc)
CPU(only)
FPGA(only)
Reference Voltage (ADC etc)
Reference Voltage
(ADC in CPU (only))