| 摘要 |
PURPOSE:To prevent the breakage of an integrated circuit chip at abnormal high temperature state using one transistor, by a method wherein a transistor is operated at voltage applying state and function of the integrated circuit with a shut-down transistor assembled thereto is disabled. CONSTITUTION:Resistors R11, R12, a diode Q11, and a transistor Q12 constitute a starter circuit 31, and collector of the transistor Q12 attracts small current at the turning ON state of the power source thereby a constant current circuit 32 is started. After the starting, collector current of a transistor Q19 flows in the resistor R12, and voltage to reversely bias between base emitter of the transistor Q12 of the starter circuit 31 is generated thereby the starter circuit 31 is turned OFF. |
