Free Circuit Diagram

Controlling the speed of three phase ac motor is done by controlling the frequency of the power line supply,  since the motor is synchronized with the line frequency. Three phase ac motor speed controller is actually nothing more than three phase sine wave power inverter with variable frequency. The three phase power inverter is a [...]

This is AC mode universal motor drive circuit. This circuit is suitable for large range of application. It uses the microcontroller to interpret the user interface that is used to select the four operating modes that are defined in hardware. Here is the circuit : As power switch, this circuit use “SNUBBERLESS” TRIAC  [...]

Electric motor has been widely used as motion control, and many  type of motor controllers  have been designed to provide variable speed drives for the motor. The best controller is the servo controller, where a precise speed control is implemented using a speed sensor in the feedback path.  The circuit of the motor controller in [...]

Stepper motor gives a simple, low cost, and accurate position control. Stepper motor can be driven by circuit mounted close to the motor, and controlled by a remote control circuit through long cable.  The interesting thing of this circuit is that the power for both motor and the driver circuit is carried over two wires, [...]

Speed control for dc motor (electric motor) can be implemented using open loop or closed loop. Closed loop controller, also known as servo controller,  or a feedback control, gives the best performance since the loop will maintain the actual speed to follow the reference. In simple application, an open loop controller can be enough if [...]

Octave shifting or frequency doubling effect for electric guitar is done by rectifying the original signal, just like AC to DC conversion inside your AC-DC power supply adapter. The circuit for this audio effect is not new, I’ve seen it on many publications. Here I present the circuit’s schematic diagram, but I’ve redesigned the circuit [...]