Smart car driver circuit

Smart car driver circuit is a full bridge driver circuit, Q1, Q2, Q3, Q4 transistor consisting of four four-arm, Q5 control Q2 and Q3 is turned on and off, Q6 control Q1 and Q4 are turned on and off , the driving circuit for the rear wheels, respectively the front direction of the driving circuit and the driving circuit. When a pin is high, 2 pin low conduction always Q1 and Q4, Q2, and Q3 is turned off, the motor drives the wheels running; When a pin is low, the two pin is high time to time As of Q1 and Q4, Q2, and Q3 is turned on, the motor drives the wheels reverse direction.