Transformerless Power Supply

Description

Any Transformerless Power Supply Circuit without using the Transformer is called a Transformerless power supply. The main component of a Transformerless power supply circuit is a Voltage dropping capacitor or X-rated capacitor, which are specially designed for AC mains. This X-rated capacitor is connected in a series of Phase lines of AC, to drop the voltage.

This is a low-current transformerless power supply for small applications. The capacitor reduces the high volt AC. D1-D4 rectifies AC to DC and second reduces ripples. The Zener diode is used to get regulated DC output. The Zener value can be changed to get other output voltages.

This power supply is suitable when designing for an application that requires low power and where cost and size are of great consideration as the expensive and bulky transformer is eliminated in this type of power supply. All the components in this circuit are sized so that the circuit can deliver 12 volts and 30mA of current at the output to the load.

Block Diagram