The CS3717A controls and drives one phase of a bipolar stepper motor with chopper control of the phase current. Current levels may be selected in three steps by means of two logic inputs which select one of three current comparators. When both of these inputs are high the device is disabled. A separate logic input controls the direction of current flow. A monostable, programmed by an external RC network, sets the current decay time. The power section is a full H-bridge