| 摘要 |
PURPOSE:To realize smooth starting by incorporating a circuit for comparing speed command value and stopping all switching elements, including those in lock protective circuit and motor drive circuit having no relation to speed control, in case of motor stop command value. CONSTITUTION:A speed command value comparing circuit 26 for a driver IC 14 compares external speed command value and if the speed command value is higher than a some value, a decision is made that the speed command value is a motor stop command value thus stopping a lock protective circuit 35, a predrive upper stage output circuit 32, and a predrive lower stage output circuit 33. Upon provision of an operational command under that state, a motor 1 is started immediately because the lock protective circuit 35 is not operating. This constitution realizes a simple drive circuit for brushless motor having low power consumption. |
