ELECTROSTATIC PROTECTION CIRCUIT AND SEMICONDUCTOR INTEGRATED CIRCUIT DEVICE

摘要

PROBLEM TO BE SOLVED: To provide an electrostatic protection circuit capable of obtaining sufficient protection characteristics against discharge of static electricity without increasing a circuit area for reducing impedance of power supply wiring and the like.SOLUTION: An electrostatic protection circuit includes: a plurality of clamp circuits connected in series between a node N1 and a node N3; a resistor R1 connected between the node N3 and a node N2; a discharge circuit being connected between the node N1 and the node N2 and brought into a conduction state when a potential difference generated between both ends of the resistor R1 is equal to a first value or more; a transistor connected to at least one of the plurality of clamp circuits in parallel; a resistor R2 connected between a source and a gate of the transistor; and a control circuit bringing the transistor into the conduction state when the potential difference generated between both the ends of the resistor R1 is equal to a second value or more.SELECTED DRAWING: Figure 3