I'd like to make a 555 PWM speed controller to drive a mosfet and switch a 240V DC motor that normally runs off a TRIAC circuit fed into a bridge rectifier. The TRIAC controller normally is set up to output 240V max from the
340V rectified mains and while it works ok has no low down torque and outputs an awful lot of RF interference.My main query is this: what's a simple effective way to generate the 12V DC or so to power a 555 IC off 340V DC?. I was mainly considering a power resistor/zener combination.