His talk at the 2018 Hackaday Superconference covers how he built a brushless DC motor and speed controller into a PCB. You can watch the newly published video after the break.

In this circuit, the renowned timer chip LM555 (IC1) is used as a PWM circuit. The whole circuit can be powered from a standard 12VDC supply, capable of sourcing ample current to the PCB drill motor.

Approx circuit of DC-51 motor speed controller (D6 and D8 are the wrong way around, and there may be more errors). And the more I looked at the circuit, the more I liked the speed controller. Update ...

Update: see the circuit and a stab at explaning it here. Safety note for folks not used to working with the mains: All electronic parts of this DC-51 motor controller are connected to live mains and ...