<p>Disclosed is a full wave drive brushless DC motor which detects zero-crossing points of counter electromotive forces respectively induced by the stator windings, pulse-shapes the zero-crossing points thus detected to obtain a pulse signal train, and measures the period of the pulse signal train thus obtained to determine a conducting phase of the stator windings in response to the period thus counted, thus being capable of supplying an electric current bidirectionally to each of the stator windings without using a position sensor for detecting a position of a rotor. <IMAGE></p>
