ON Semiconductor's STK672 2-Phase Stepper Motor Drivers are hybrid ICs for use as a unipolar, 2-phase stepper motor driver with PWM current control. They feature the use of A, AB, B and BB 2-phase input signals. This is accomplished with a built-in current resistor. The motor current is set by the voltage on the VREF pin. In addition the STK672 has various protective functions against over-current and over-heating. Typical applications include multi-function printer, document scanner, auto trading machine, and vending machines.