Hybrid Stepper Motor Driver Circuit

Stepper motor vs servo motor.

Hybrid stepper motor driver circuit.

When stopped but energized a stepper short for stepper motor holds its load steady with a holding torque. To overcome the inductance and switch the windings quickly one must increase the drive voltage. The stepper motor drive is a dumb piece of electronics unless and until you program the microcontroller to give signals correctly to the stepper motor via the driver. Now as shown in the circuit diagram the 555 circuit here is to generate clock or the square wave.

A stepper motor driver is a circuit that takes the pulse signals from a controller and converts them in to stepper motor motion. In this project we have designed a simple 12v stepper motor driver circuit using 555 timer ic acting as a controller a cd4017 decade counter acting as the driver along with few other components. A stepper motor is a digital version of the electric motor. The figure shows the circuit diagram of two stage stepper motor driver.

When a phase is to be energised the dc source is connected to the phase by a semiconductor switch s fig. The phase current builds up at the rate decided by the phase winding s electrical time constant. A stepper motor can operate in many modes like full step wave drive or half stepping please refer the article on stepper motor for the sequence of steps. A drive circuits for stepper motor is usually driven from a low voltage dc source.

The rotor moves in discrete steps as commanded rather than rotating continuously like a conventional motor. The frequency of clock generation in this case cannot be kept constant so we need to get variable speed for the stepper motor. The widespread acceptance of the stepper motor within the last two decades was. Torque curves may be extended to greater speeds if the stator poles can be reversed more quickly the limiting factor being a combination of the winding inductance.