Protection circuit for semiconductor integrated circuit that can discriminate between program voltage and static electricity

摘要

A current when static electricity intrudes is passed by a first circuit portion composed of a series circuit including a fuse element and a resistor until a program voltage is applied to a program voltage terminal, and the fuse element is fused when the program voltage is applied. A current for breaking the fuse element is passed when an N-type MOS transistor turns into a second breakdown state by a gate voltage from a second circuit portion.