In this post I have elaborately explained how to build simple transformerless LED bulb circuits using many LEDs in series and powering them through current controlled capacitive power supply circuit. Safety Note: These circuits operate directly from mains AC voltage without galvanic isolation, meaning live components carry high voltage when energized. Standard electrical safety practices […]
Circuits
AC Motor Speed Controller Circuits using Back EMF
In this post I have explained a few circuit diagrams for building AC motor speed controller circuits using back EMF concept. Working Principle of AC Motors So now, all those home type appliances like electric drill machines, sander machines, sewing machines, food mixer machines, etc. they all are mostly using that AC motor which is […]
Motor Protection Circuits – Over Voltage, Over Heat, Over Current
In this post I have explained a few DC motor protection circuit from harmful conditions like over voltage and under voltage situations, over current, overload etc.. DC motor failures are commonly experienced by many of the users, especially in places where the relevant motor is run for many hours a day. Replacing motor parts or […]
Very Simple BLDC Motor Driver Circuits using Back EMF
In this post we investigate what’s a BLDC motor and subsequently I have explained regarding the design of a sensorless BLDC motor driver circuit. BLDC CPU Fans Seen those fast moving fans in CPUs, voltage stabilizers, DVD players, and other similar equipment, which work with utmost efficiency, consuming minimum space, current and yet are able […]
5 Simple DC Motor Speed Controller Circuits Explained
A circuit which enables a user to linearly control the speed of a connected motor by rotating an attached potentiometer is called a motor speed controller circuit. 5 easy to build speed controller circuits for DC motors are presented here, first one using MOSFET IRF540, second one using IC 555, the third concept with IC […]
Simple H-Bridge Circuits Using BJTs and MOSFETs | No Need of Driver ICs
An H-bridge is one very useful circuit arrangement which lets us reverse the polarity across a load, so now with one DC supply we can make current flow through the load in both directions alternately. Because of that, these H-bridge circuits get used in many places like DC to AC inverter circuits, transformer drivers, bidirectional […]





