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
LM324 Quick Datasheet and Application Circuits
In this post we are going to take a look at the popular LM 324 IC. We will be looking at the pin configuration, its important features and its technical specifications and finally we will be looking at some of the fundamental application circuits using LM 324. If you are looking for a low voltage […]
3 Best Transformerless Inverter Circuits
As the name suggests, an inverter circuit that converts a DC input into AC without depending on an inductor or a transformer is called a transformerless inverter. Since an inductor based transformer is not employed, the input DC is normally equal to the peak value of the AC generated at the output of the inverter. […]
4 Simple Proximity Sensor Circuits – Using IC LM358, IC LM567, IC 555
Video Demonstration An IR proximity sensor is a device which detects the presence of an object or a human when it is within a predetermined range from the sensor, through reflected infrared beams. Three useful proximity sensor concepts are explained here, the first concept is based on an ordinary opamp LM358, the second one using […]
3 Smart Laser Alarm Protection Circuits
In this post I have explained the making of 3 simple yet effective smart laser alarm protection circuit using the IC 555, for securing a specified restricted zone from human interventions. The idea was requested by Mr. Collins. Circuit Objectives and Requirements 1) The Design Parts List IC 555Pinouts Circuit Operation The proposed smart yet […]
5 Simple Audio Mixer Circuits Explained
The explained 5 circuits below are universal simple audio mixer circuits, that may be customized and upgraded to 5 channel or even 10 channel mixers, as desired by the user. Contributed by: Anil Rao. Stereo Audio Mixer The operation stereo audio mixer circuit shown below is straightforward: If a mic is “being used,” its output […]





