| 摘要 |
PURPOSE:To protect a hybrid IC without excessive protection by a method wherein a conductor of output circuit of a hybrid IC is partly narrowed in width to fix a heat sensitive element on the narrowed part detecting a temperature rise and disconnecting the output circuit current. CONSTITUTION:The complementary output transistors 1, 2 are fixed on a copper foiled conductor 11 of a hybrid IC circuit substrate 10 through the intermediary of a heat sink 12 connecting to the conductor 11. A narrowed detecting part 13 is provided on the conductor 11 connected to an emitter adhering to an Si planar type transistor 3 to detect 4 voltage fluctuation due to temperature change disconnecting the current of the output transistors 1, 2. In the concrete, a relay 5 is inserted into the power supply line between the element 2 and the driver step thereof driving the relay 5 by means of the output of a detecting circuit 4. In such a constitution, the transistors 1, 2 are not actuated by an instantaneous high signal input due to a bit of time lag until the time to detect excessive current while preventing excessive protection and simplifying the device by eliminating a conventional high wattage resistor. |
