2 Solid-State IC Based 220V Adjustable Power Supply Circuits

A couple of simple yet efficient 220V operated transformerless 50V adjustable solid-state power supply circuit using a single IC SR087 is discussed in the following article. The design does not depend on high value capacitors or inductors and yet is capable of delivering 100mA current to the attache load. Circuit#1: Main Features and Board Layout … Read more2 Solid-State IC Based 220V Adjustable Power Supply Circuits

1.5V Power Supply Circuit for Wall Clock

The post presents a simple transformerless 1.5V DC power supply circuit which can be used for powering wall clocks directly from mains, and also keep a stand by back-up cell fully charged for enabling an uninterrupted operation of the clock even during mains failures. The idea was requested by Cheekin Warning: This circuit is not … Read more1.5V Power Supply Circuit for Wall Clock

Transformerless 0-400V Power Supply Circuit

A cool 0-400V variable transformerless power supply circuit can be built using just a single chip LR8, and a few resistors. The IC features  a built in current control stage which makes the design extremely safe even for critical electronic circuits. How LR8 IC is Designed to Work The IC LR8 is quite similar to … Read moreTransformerless 0-400V Power Supply Circuit

Zero Crossing Transformerless Power Supply Circuit

The post explains the importance of a zero crossing detection in capacitive transformerless power supplies in order to make it completely safe from the mains switch ON inrush surge currents. The idea was proposed by Mr. Francis. Technical Specifications I have been reading about the transformer less power supply articles on your site with great … Read moreZero Crossing Transformerless Power Supply Circuit

Voltage Stabilized Transformerless Power Supply Circuit

The post explains how an ordinary capacitive power supply may be transformed into a surge free voltage stabilized or variable voltage transformerless power supply applicable for almost all standard electronic loads and circuits. The idea was requested by Mr. Chandan Maity. Technical Specifications If you remember, I communicated you sometime before with comments at your … Read moreVoltage Stabilized Transformerless Power Supply Circuit

Switching Transformerless Power Supply using IC 555

A simple yet smart solution is implemented here using IC 555 in its monostable mode to control in rush surge in a  transfomerless power supply via a zero crossing switching circuit concept, wherein the input power from the mains is allowed to enter the circuit only during the zero crossings of the AC signal, thereby eliminating the … Read moreSwitching Transformerless Power Supply using IC 555