Pushing the start button activates a motor controller relay (or contactor ... Instead, the controller also manages a DC-to-DC converter that charges the 12-volt battery using the high-voltage battery.

[Davide Gironi] shows us how to implement a sensorless brushless DC motor controller (sensorless BLDC) using an ATmega8 microcontroller. In order to control a BLDC motor you need to know its rotati… ...

The controller can power other small PCB drills, as well as other devices containing small 12 Volt DC motors, although some changes to component values may be necessary.

In the foreground a 12V DC motor is held in place with an electrical conduit clamp. This connects to the stepper motor being tested using a segment of rubber tube.