In the application of driving circuit for motors, users may encounter the problem that motor interferes with voice IC working. In some cases, users even hold the motor to stop its rotating to make sure that the voice IC can work normally under strong noise condition.
Since the operating current of motor is large and most motors in applications are low quality, strong noise occurs while motor operating. The noise would interfere with voice IC working in the ways of common-mode or different-mode, which makes IC have logic error.
To solve this problem, please see the following methods.
1. Add a decouple component in circuit, add a 102 capacitor and a 10k resistor between trigger pin and ground. And add some capacitors and inductors on terminals of motor to eliminate noise.
2. Add delay time by programming. (E.g. add 200ms Delay time during motor forward to reverse rotating)
3. Arrange the wires route of motor and power supply. Please see the figure below, motor and speaker should not be connected through PCB but directly connected to batteries box. Besides, motor wires and other wires should be kept apart.
