Maxim Integrated Products, Inc.
METHOD AND CIRCUIT ARRANGEMENT FOR CONTROLLING A STEPPER MOTOR

Abstract:

Described is a method and a circuit arrangement for controlling a stepper motor in a voltage-controlled or voltage-regulated operating mode, having a bridge circuit provided for a motor coil (A) with semiconductor switches (HS1, HS2, LS1, LS2) for applying a first and a second PWM voltage (U(LA1), U(LA2)) having opposite polarity to the motor coil (A) and having a charge pump for switching at least the high-side semiconductor switch (HS1, HS2) of the bridge circuit. Because the charge pump must wait for a blocking or dead time before a further semiconductor switch can be switched after switching a first semiconductor switch, the time interval between a rising edge of one of the two PWM voltages and a subsequent rising edge of the respective other PWM voltage is increased at least until the blocking or dead time of the charge pump has elapsed.