Power Supply Pcb - Brother PT-1800 Service Manual

3.3 POWER SUPPLY PCB

Figure 3.3-1 shows a circuit diagram of the power supply PCB. Capacitor C1 is for the
logic circuit; capacitor C2 is for the thermal print head and DC motor drive sources.
Connecting the AC adapter plug with the AC jack J1 cuts off the power fed from the
batteries and feeds power from the AC adapter.
Figure 3.3-2 shows the polarity of the AC adapter plug.
Figure 3.3-1 Power Supply PCB
Figure 3.3-2 AC Adapter Plug
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