Semiconductor ic

Abstract

Abstract PURPOSE:To protect an FET gate from an instantaneous high voltage caused by a static electricity charged on a human body by a method wherein an NPN-type transistor and an MOS transistor are provided between an input terminal of MISFET, with which an IC is constituted, and an earth terminal. CONSTITUTION:The input terminal T is connected to a gate of the MISFET element 2 to be protected and the earth terminal E is connected to a source or a drain of the element 2 and the element 2 substrate. Then, in order to protect the element 2 from an instantaneous high voltage, a transistor emitter is connected to an input terminal and a collector is connected to the earth terminal E using an NPN-type transistor 8 and an MOS transistor 9. In addition, the source and drain of the MOS transistor 9 are connected between the base of the transistor 8 and the earth terminal E and the transistor 9 substrate is grounded. As a result, when an overvoltage is applied to the input terminal, the transistor 8 bypasses it instantly and no damage is given to the element 2 gate.

Inventors

• 👤 Takeo Komatsu
• 👤 Toshihiko Akiyama

Bibliographic Details