Circuit Explanation; Power Supply Circuit - Casio TK-6500 Service Manual

6.CIRCUIT EXPLANATION

6-1. Power supply circuit

The power supply circuit provides the following voltage for the main circuit.
Output Pin No1-----
Output Pin No.2----
Output Pin No.3----
Output Pin No.4----
The power switch SW1 is located at the right side of the lowercase.
After connected the power plug into AC outlet and turn on the SW1, the transformer T1 will
genarate the about AC33V to secondary side. Then, after rectifier circut, the VC1 (DC32.3V)
is supplied to the VC line for display power (for the drive of display tube. Not for LED model.)
The IC2 is the shunt regulator for the control of Q1 transistor. This circuit is genarate the
VC2 (DC24V) for the printer power. The IC1 is regulator for 5V power supply.
Power supply PCB E445-S1
VC1 (DC32.3V): To the VC line for the Display power. (Not used for TK-6500)
VC2 (DC24V): To the Vp line for the printer power.
VLED (DC5.85V): To the Vcc,Vcc2 and Vdd for the logic circuit power.
GND: Signal GND.
Power switch SW1
Voltage selector
NOTE: Do not turn the selector to
avoid the voltage selection mistake.
(Not used for USA and Cabada)
- 9 -
NOTE: Voltage selector is not used for USA and Canada.
F3 is not used for TK-6500.
Power SW1 cover