Dc Motor Driver Circuit - Brother PT-2300 Service Manual

3.2.6

DC Motor Driver Circuit

Fig. 3.2-8 shows a driver circuit of the DC motor which feeds tapes and ink ribbon.
Through PG3, the CPU issues a start/stop control signal to the motor driver circuit. Fig. 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.
Fig. 3.2-8 DC Motor Driver Circuit
III-8