| 摘要 |
<p>PURPOSE:To prevent hunting due to inertia of a motor, in a motor driving device which performs PWM control, by forming a circuit which shortcircuits its motor while a PWM signal during the PWM control is off so as to afford braking force to a motor. CONSTITUTION:In a motor driving device fit for an electric power steering device and the like, a general H bridge circuit for controlling its motor has respective transistors Tr 1, 3 and 2, 4 in the lower and upper sides thereof and a motor 5. In this case, Tr 2 is a made to be on during the period when the Tr 1 is off, while the Tr 4 is made to be constantly on as usual. Regenerative electric current is thereby guided to pass through the motor 5 during the period when the Tzr 1 is off, then dynamic braking electric current is guided to pass therethrough to make it possible to brake the motor 5. Respective signals sent to the gate terminals TM 1-TM 4 of the Tr 1-Tr 4 are generated from a logic circuit or a microcomputer.</p> |
