| 摘要 |
PURPOSE:To prevent electrostatic breakdown without affecting normal circuit operation by connecting a second electrode for a diode element to a base in a transistor element and connecting a first electrode to an emitter. CONSTITUTION:A base electrode 27 being in ohmic-contact with a base region 16 in a transistor element 2 and a second electrode 25 for a C-E short diode element 5 are connected, and an emitter electrode 28 and a first electrode 26 are connected to an emitter region 18. Input signals are transmitted over the transistor element 2 through pads 3 from external lead terminals 4 on normalcy. That is, since the diode element 5 as a protective element is connected between a base and an emitter while polarity is reversed, input signals do not flow through the diode element 5, and no circuit operation is affected. When surge voltage is applied to the external terminals, surge energy applied between the base and the emitter in the transistor element 2 is let escape to each P-N junction in the diode element 5 to a certain extent, and the transistor element 2 and the diode element 5 mutually absorb surge voltage, thus increasing breakdown voltage, then preventing electrostatic breakdown. |
