ON Semiconductor's STK672-6xx family of devices are hybrid ICs for use as unipolar, 2-phase stepper motor drivers with PWM current control. The devices include a built-in controller and are based on a unipolar constant-current PWM system. The STK672-6xx devices support application simplification and standardization by providing a built-in 4-phase distribution stepping motor controller. Using these devices, the motor speed can be controlled with only a clock signal. The use of these hybrid ICs allows designers to implement systems that provide high motor torques, low vibration levels, low noise, fast response, and high-efficiency drive.