L2720/2/4
Figure 12 : Bidirectional Speed Control of DC Motors
2R3 . R1
For circuit stability ensure that RX >
RM
where RM = internal resistance of motor.
VS
2R3 . R1
The voltage available at the terminals of the motor is VM = 2 (VI −
) + |RO|. IM where |RO| =
2
RX
and IM is the motor current.
Figure 13 : VHS-VCR Motor Control Circuit
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