| 摘要 |
PURPOSE:To effectively detect an overcurrent state in a rapid response by connecting a current detecting resistor to a sample-holding capacitor through a sample-holding switch. CONSTITUTION:A sample-holding switch 20 is turned ON synchronously with the ON period of a switching element 3, and the terminal voltage of a current detecting resistor 13 during ON period is held in a smaple-holding capacitor 21 as a sample. An output signal of high level is supplied from a comparator 17 to a controller 12 in case of the overcurrent state. Thus, the pulse width of a control pulse output from the controller 12 is narrowed to limit the load current to the prescribed value or lower. |
