In this post I have explained how to make a simple variable power supply circuit using transistor 2N3055 and some other passive components. It includes variable voltage and variable current feature, fully adjustable. Main Specifications 1) Adjustable from 0-30V, 0-60V, and 0-100V, and 500mA to 10 Amp as per user preference 2) Short Circuit Protected […]
Power Supply Circuits
Simple Crowbar Circuits for Over-voltage Protection
A handful of simple DC over voltage protector crowbar circuits are discussed in this article. I have explained the working of each crowbar circuit through the following explanation. What is Crowbar Circuit If you are wondering what is a crowbar circuit, the definition is simple. It is a circuit network where a transistor or an […]
Regulated, High Current Power Supply Circuit
The circuit I have explained below can be used for applications that require stringent voltage regulations and ripple rejection criteria. The transistor pair are configured such that all residual ripple factor are perfectly rectified. Circuit Operation The circuit below shows a simple way of acquiring a perfectly regulated and stabilized high current DC voltage output using ordinary transistors. The circuit […]
4 Simple Transformerless Power Supply Circuits Explained
In this post I have explained 4 easy to build, compact simple transformerless power supply circuits. All the circuits presented here are built using capacitive reactance theory for stepping down the input AC mains voltage. All the designs presented here work independently without any transformer, or no transformer. The Transformerless Power Supply Concept As the […]
How to Use LM317 for Making a Variable Power Supply Circuit
In this post I will elaborately explain how to build a simple LM317 based adjustable power supply circuit using minimum number of external components. As the name suggests a variable power supply circuit provides the user with a range of linearly varying output voltages through a manually controlled potentiometer rotation. A LM317 is a versatile […]
How to Calculate Transformerless Power Supply Circuits
In this article I have explained how to calculate resistor and capacitor values in transformerless power supply circuits using simple formulas like ohms law. Analyzing a Capactive Power Supply Before I have explained the formula for calculating and optimizing resistor and capacitor values in a transformerless power supply, it would be important to first summarize […]