Low-power circuits commonly use transformerless power supplies. However, the use of earth grounds in many of these circuits creates a serious problem that is often ignored. The very popular Microchip ...

This circuit will supply up to about 20ma at 12 volts. It uses capacitive reactance instead of resistance; and it doesn’t generate very much heat.The circuit draws about 30ma AC. Always use a fuse and ...

This 12 Volts transformerless power supply take advantage of the fact that a Zener diode is also a normal diode that conducts current in the forward direction. During one half wave, the current flows ...

For one-off projects or prototyping, it’s not too hard to find a wall wart or power supply to send a few joules of energy from the wall outlet to your circuit. Most of these power supplies use a ...