Traces: pre-regulated voltage (blue), output voltage (green), buck PWM (orange). ~80% efficient.
A transformerless design that doesn't waste 150+ volts straight across a regulator, using a buck converter as the key component. As always, a 100Hz converter and its component values are extremely unrealistic, but higher than that it takes far too long to stabilise in simulation.
Mains rectifier (top left), buck converter (top centre), linear regulator (top right), basic PWM (bottom).
