| 摘要 |
PURPOSE:To prevent a load circuit such as an oscillating circuit from heating itself abnormally and breaking down, by limiting a supply current to the load circuit. CONSTITUTION:The collector of an NPN transistor TR2 is connected to the side of a power source 1 through a coil L, to the emitter through a resistance R4, and also to the base through a resistance R5 for current supply. The emitter is connected to the intermediate tap (a) of the primary winding of the transformer T of an oscillating circuit through a resistance R6. The base is grounded through a decoupling C5, and also connected to the oscillating circuit side of the resistance R5 through diodes D1 and D2 coupled in series in a forward direction, namely, by connecting the anode to the base side. Consequently, even if the oscillating circuit as a load decreases in impedance owing to a short- circuit, the supply current to the load is limited and a resistance as a load is prevented from heating itself abnormally and breaking down. |
