Free Circuit Diagram

A DC-to-DC step-up converter is traditionally implemented using transformer, working by converting the DC voltage to AC Voltage, step-up it using transformer, then rectify and filter the transformer’s output to  get a higher DC voltage. Using a switching method, we can step-up a voltage without a transformer. We just need an inductor which is driven [...]

Our reader Andrea (andrea[dot]perugia[-at-]gmail[dot] com) sent his circuit to us, and he creates the circuit for educational intent. The main purpose is to show that you can toggle an output state electronically, although physically you use only a push button switch. Here is what he said about the cicuit : This simple [...]

This transistor tester is very helpful if you need to sort bulk transistors. In  some market, if you know where to find it, sometimes you can get transistors sold in kg unit, not in single peaces unit. You can buy 1 kg of transistors with really cheap prices. Don’t be too happy right now because [...]

This circuit is similar with our previous dimmer circuit, but the gate control is full-wave rectified using diode bridge. This circuit can be used to replace electric switch for your incandescent lamp, brushed motor, soldering iron or heater. Here is the schematic diagram of the dimmer switch: Please note that his dimmer switch [...]

This circuit is made to be an alarm, both for home and handbags. If it is installed for home it will placed on door or windows, and if it is installed for bags or hanbags it will placed in the bag. This circuit consists of a small magnet and a reed switch. If the magnet [...]

The monostable flip flop is a electronic circuits that is used to produce a single pulse each time it is triggered. Sometimes, this circuit called a ‘one shoot’. This circuit is very useful, for example it can used to produce a delay for timing applications or debounce a mechanical switch so that only one rising [...]