| 摘要 |
PURPOSE:To recover an IC, which is latch-upped by electrostatic noise, to the normal condition by interrupting the supply of power to an integrated circuit group when the output of a detection circuit is lower than the set value. CONSTITUTION:If a CPU1 is brought into a lutch-up state when surge voltage, generated by electrostatic noise and the like, is applied to the CPU1 through a transistor 2, source potential decreases remarkably. This state is detected by a detection circuit IC 4, transistors 2 and 6 are turned off, the power supply to the CPU1 is interrupted, and the CPU1 is reset. As a result, the breakdown of the CPU1 and the erroneous operation of the means to be controlled by the CPU1 can be prevented. Also, when the generation of surge voltage is stopped, this state is detected by the detection circuit IC 4, the transistors 2 and 6 are turned on, and the source voltage is supplied to the CPU1. As a result, the CPU1 recovers its normal function. |
