Free Circuit Diagram

The circuit below is the basic for standard symmetrical power supply. If your circuit need high current then this circuit is suitable. Here you can see the circuit’s schematic diagram. You need a center-tapped transformer to build this symmetric power supply. This power supply circuit is widely used in op-amp application, as [...]

Basic interruptible Power Supply Circuit consist of regular power supply adapter and battery connection. This basic system is a “hot” battery connection, meaning that there is no switching mechanism in connecting and disconnecting the battery, the battery is always connected! This hot connection is very simple to implement and very robust because there would [...]

For any electrically conductive liquid level measurement, this single chip circuit is very compact and simple. This circuit is an ac excited fluid level sensor, which uses alternating current to provide biasing for the sensor probe to avoid electrolysis of the probes.  This ac excitation makes the sensing probe has longer lifetime. This circuit can [...]

Building electronic circuit tutorial (DIY: do it yourself project) is presented in this video. You can learn the basics about schematics and how they are used in electronics in this free home maintenance video.

This sine wave generator is adjustable between 15 Hz to 150 kHz. The circuit is basically a Wien-bridge oscillator, with multiple capacitor selection. Here is the schematic diagram: A stereo 10k potentiometer is used to control the frequency. The dashed line connecting these two potentiometers show that both potentiometer has single axis.

Integration is one of basic signal processing that can be done in analog domain. Using operational amplifier (op-amp), integration operation can be done with very simple circuit with very high accuracy. Here is the schematic diagram of an integrator circuit: The resistor R2 should have the same value with R1 since R2 [...]