Free Circuit Diagram

This is JFET-bipolar cascode circuit. It will provide full video output for the CRT cathode drive. The gain of this circuit is about 90. Here is the circuit : This circuit employs 2N4091 JFET to solve Miller capacitance problems using cascode configuration. It will alow direct drive from the video detector. [...]

A fast peak detector similar but faster than previous peak detector, can be implemented using open loop configuration. Here is the schematic diagram of the circuit: In this  design, D1 is the detector diode and D2 is a level shifting or compensating diode. A load resistor RL is connected to – 5V and [...]

Classic LED Flasher Circuit This LED flasher circuit is a classic two transistor flip flop. This flasher circuit is very popular and it’s usually the first circuit to build when starting electronic circuit building hobby. Here is the schematic diagram of the famous LED flasher circuit: How LED Flasher Circuit Works [...]

The high durability nature of a light emitting diode (LED) make it suitable for ON/OFF indicator application. Because the limitation on low operating voltage, LEDs are normally applied on low voltage application.  Fortunately, there is a simple method to apply LED indicator for high powerline voltage: reactance of a capacitor can be used to limit [...]

Closed Loop Motor Control Closed loop (servo) control is used to make a constant speed motor control. Constant speed means that the speed of the motor will be kept constant although the load is change, or even when the electric supply voltage is also changed.  The circuit maintain the speed at a constant value [...]

Notch filter is known as band-cut filter or band-reject filter. The fuction of this filter is to remove some frequency portion of a signal. The schematic diagram of this filter circuit, a second order notch filter is depicted in the figure below. The formula is actually complicated, but by taking the R3=R4 and [...]