| 摘要 |
PURPOSE:To prevent upper and lower transistors from being simultaneously turned ON by connecting the base of the upper transistor through a resistor to a ground or a predetermined voltage. CONSTITUTION:Transistors Q12, Q22 are controlled ON, OFF by a PWM circuit 2. The PWM circuit 2 selects the Q12, Q22 by a controller 1. When the transistors Q12, Q22 are turned OFF, a current of a motor winding 3 is fed through diodes D11, D21 to a power source voltage terminal Vcc. In this case, charges are stored in the bases and collectors of the transistors Q11, Q21 and Q13, Q23, respectively. The charges are discharged through resistors R12, R22 to a ground point. Thus, it can prevent the transistors Q11 and Q12, Q21 and Q22 from being simultaneously turned ON. |
