| 摘要 |
PURPOSE:To stop the drive while a transistor(TR) is turned off quickly when an input is stopped even if the length of an on-pulse is changed by operating an off-pulse drive circuit only when the off-pulse generating circuit generates an off-pulse and a current detection means detects a current. CONSTITUTION:A current detection means 12 detecting a current flowing to a transistor(TR) 10 and a control means 4 activating an off-pulse drive circuit 5 only when an off-pulse generating circuit 3 generates an off-pulse and the current detection means 12 detects a current are provided to the title circuit. Thus, the off-pulse drive circuit 5 is controlled depending whether a current flows to the TR 10 or not. Thus, even when the length of the on-pulse is changed, the off-pulse drive circuit 5 is acted effectively and when the input of the on-pulse is stopped, the TR 10 is turned off quickly to stop the drive. |
