Patent ID: 6128173
Filing Date: 2000-10-03
Classification: H01L

Abstract:
A semiconductor integrated circuit device comprisingat least one signal terminal supplied with an input signal;a first power supply terminal connected to a first power supply line and supplied with a first power voltage;a second power supply terminal connected to a second power supply line and supplied with a second power voltage different from said first power voltage;a main circuit supplied with said input signal for producing an output signal and includinga first field effect transistor having a first gate insulating layer to which is applied a first potential difference between said first power supply line and said second power supply line, said first field effect transistor having a first break-down voltage, andat least one second field effect transistor having a second gate insulating layer to which is applied a second potential difference smaller than said first potential difference; anda protective circuit for preventing said main circuit from a static charge, and includinga first protective sub-circuit having p-n junctions spaced from each other, connected in series between said first power supply line and said second power supply line, reversely biased and providing a current path between said first power supply line and said second power supply line due to a punch-through or a break-down of said p-n junctions under application of said static charge at a second voltage lower than said first break-down voltage.