Abstract: A pulse wave inverter circuit having two PNP transistors and two NPN transistors which are arranged such that the transistors are connected in the form of a bridge. The transistors are turned on and off so as to produce a pulse wave power. A first transistor of the four transistors is connected to a positive terminal of a D.C. power source; a second transistor is connected to a negative terminal of the D.C. power source; a third transistor, which is PNP transistor, has its emitter connected to the positive terminal of the D.C. power source; and a fourth transistor, which is NPN transistor, has its emitter connected to the negative terminal of the D.C. power source. The four transistors are turned on and off by a single switching signal which is fed to the bases of the above-described first and second transistors. This inverter circuit is suitable for driving a brushless motor.