Circuits & Schematics Beginners

The exposure tester in this Design Idea measures the on time of a light source, whether an LED, an incandescent lamp, a halogen lamp, or another source. It can be made with an ordinary stopwatch and a few simple components (figures 1 and 2). An ...

Included among the many applications for pulse-width modulation (PWM) are voltage regulation, power-level control, and fan-speed control. A PWM circuit for such systems can be implemented with three op amps on a single quad-op-amp chip (Fig. 1). ...

Story The high temperature of the power components is a known phenomenon in electronics. To overcome this challenge, the designers mount heatsinks on the components to dissipate the heat, however, in many commercial and home appliance devices, the ...

Fig 1’s circuit, which was developed to monitor the traffic of bumblebees into and out of the hive, differentiates “a-to-b” motion from “b-to-a” motion. When used with an optical decoder, the circuit distinguishes ...

Streetlights, emergency lights, and security lights must automatically turn on when it gets dark. You base the control circuit on the resistance of a photoresistor or another LDR (light-dependent resistor) that varies with light intensity. An ...

If someone in your family has the habit of not completely closing a drawer or perhaps the food freezer’s door you’ll appreciate this design. It senses an ajar door and, if the situation isn’t corrected within 20 sec, sounds a ...

Sometimes, you may need to make a DC/DC converter with minor components that can handle small loads. In this article, we are going to make something like that. This DC/DC converter using transistor has only a few components and can handle small ...

Safety fuses or fusible links see wide use in modern electronic equipment to protect the load and the power supply especially batteries against short circuits and excessive load current. Fuses are inexpensive and simple, and a wide range of parts ...

This 8051 microcontroller-based control circuit adjusts the speed of a small permanent-magnet dc motor via photosensors (Figure 1). The circuit can find applications in light-tracking systems for adjusting tracking-motor speed depending on the ...

Jeremy S. Cook hackster.io In this project, I am showing you how to build a digital laser tachometer based on Arduino for around 10$. If you need to measure rotational speed, you can just buy it or do it yourself and learn something while building ...