Free Circuit Diagram

This circuit generates a square-wave which is useful as a clock signal or AC drive for the excitation of sensors. this article presents a square-wave oscillator. This circuit requires no external components unless the bypass capacitor. Figure below shows the circuit, the output frequency and a scope shot of the output waveform. [...]

Using a single supply quad comparator LM339, LM239, LM2901, LM2901V, NCV2901, or MC3302, we can build a square-wave oscillator with simple circuit and formula. Here is the schematic diagram: This circuit is suitable if you need  many square-wave oscillators in one circuit, since the quad packaged comparator provide four comparators in one single  [...]

Sawtooth wave oscillator is used in cathode ray tube deflection circuitry, in a PWM modulator, or in a analog to digital conversion. You can also use it in your own design, only your imagination can limit its application. Here is one example of the circuit: The frequency is determined by C1, R1, R2, [...]

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 [...]

PLL oscillator is used to get very stable frequency woth very low distortion of sine wave output. The stability is equal to crystal-based oscillator, and the low distortion level of the sine wave output is equal to LC based oscillator. The method of PLL control in PLL oscillator is done by adjusting the frequency of [...]

A simple half-wave peak detector using a single transistor is very compact and low cost, but if the application require precise detection for signal under 100mV then that circuit become useless. Here you can use more precise half-wave peak detector circuit using only a single op-amp with few passive components. Look at the circuit’s schematic [...]