| 摘要 |
PURPOSE:To protect a power circuit from excess current at the time of the lowering of a load impedance and the short-circuiting of the load, by inserting a diode into a space between the power-ON/OFF terminal of a micro-computer in a stand-by circuit, and a power output line. CONSTITUTION:With a power circuit provided with a switching regulator 4, its controlling circuit 5, and a stand-by circuit 12, a diode 13 is inserted into a space between the power-ON/OFF terminal 10 of a micro-computer set in the standby circuit 12, and a power output line. The direction of the diode 13 is set so that it may be turned ON at the time of the lowering of the impedance of a load 11 and the short-circuiting of the load. As a result, when the load short-circuiting or the like is generated, then the diode 13 is turned conductive, and the switching regulator 4 is turned OFF via the controlling circuit 5, and so the power circuit can be protected so that excess current cannot flow through the circuit. |
