| 摘要 |
PURPOSE:To prevent electrostatic breakdown of an integrated circuit by a method wherein an impurity region of a polarity different from that of a substrate is provided in the neighborhood of a circuit which clamps the substrate and the first terminal by voltage. CONSTITUTION:The titled circuit for the semiconductor integrated circuit comprises a transistor 31, the collector of which is connected to the first input- output terminal 30 of the IC, a resistor 32 one terminal of which is connected to this transistor 31, and the second input-output terminal 34 to which the cathode of a diode 33 is connected. When a static electricity is impressed so that the first input-output terminal 30 of this circuit comes into a higher voltage than the second input-output terminal 34, a voltage clamping circuit consisting of the transistor 31 and the resistor 32 operates, and the diode 33 is biased in a forward direction. Therefore, the voltage between the input-output terminals 31 and 34 is clamped by a voltage larger by a factor of diode forward directional voltage VF, and accordingly the IC is protected. |
