| 摘要 |
PURPOSE:To prevent a flowing through a ground of one part of a normal signal, and to protect an internal circuit from external surge voltage by forming a second metallic film to a first metallic film connected to an external wiring on a substrate through an extremely thin gap. CONSTITUTION:An extremely thin gap 32 is shaped at the center of a high resistance film 31 formed so as to connect a pad section 22 and a metallic film 24, so that direct conduction between the pad section 22 and the metallic film 24 is interrupted. In such a constitution, even when a normal signal of several V - several tens of V is applied to the pad section 22, the pad section 22 and the metallic film 24 are interrupted owing to the gap 32, and currents do not flow through the metallic film 24 from the pad section 22. When external surge voltage of several hundreds of V - several tens of kV is applied to the pad section 22 from an external terminal 13, the gap 32 is substantially nothing, thus discharging surge voltage, then protecting an internal circuit. |
