Motor Driver Circuit - Brother PT-1800 Service Manual

3.2.5

Motor Driver Circuit

Figure 3.2-8 shows a driver circuit of the DC motor which feeds tapes and ink ribbon.
Through P10, the CPU issues a start/stop control signal to the motor driver circuit.
Figure 3.2-9 shows the control signal and drive current waveforms.
The DC motor integrates an electronic governor circuit which handles the variation of the
drive source voltage (VBT), in order to keep the rotation speed constant.
Figure 3.2-8 Motor Driver Circuit
Figure 3.2-9 Motor Control Signal and Drive Current
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