A PIR motion sensor alarm is a device which detects the infrared radiation from a moving human body and triggers an an audible alarm. In this post I have explained 5 simple motion detector circuits using op amp and transistor. We also discuss the pinout details of the standard passive infrared (PIR) sensor RE200B. We […]
Circuits
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 […]
Simple Frequency Meter Circuits – Analogue Designs
The following simple analogue frequency meter circuits can be used for measuring frequencies which may be either sine wave or square wave. The input frequency which is to be measured must be at least 25 mV RMS, for optimal detection and measurement. The design facilitates a relatively wide range of frequency measurement, right from 10 […]
5 Useful Motor Dry Run Protector Circuits Explained
The 5 simple dry run protector circuits presented here shows simple methods by which insufficient water conditions inside an underground tank can be sensed without introducing probes inside the underground tank, and thus preventing any possibility of motor dry running. The circuit also incorporates an overhead water overflow control feature. The idea was requested by […]
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 […]
9 Simple Sine Wave Generator Circuits Explored
A sine wave generator is actually a sine wave oscillator circuit which generates an exponentially rising and falling sinusoidal waveform. The 9 simple sine wave generator circuits presented in the following article are easy to build, since they incorporate a small number of ordinary electronic components, and can be used for generating an exponentially varying […]