Patent ID: 6229180
Filing Date: 2001-05-08
Classification: H01L

Abstract:
A MOS type semiconductor apparatus comprising:a semiconductor substrate;a main MOS type semiconductor device including a control portion of a metal-oxide film-semiconductor (MOS) structure;a first output terminal and a second output terminal to which two outputs of said main MOS type semiconductor device are connected;a control input terminal to which a control input of said main MOS type semiconductor device is connected;an internal control circuit connected between said control input terminal and the control input of said main MOS type semiconductor device; anda protecting device connected between said control input terminal and said first output terminal, for protection against overvoltage, said protecting device comprising a first branch including a first Zener diode comprising a polysilicon layer deposited on an insulating film over said semiconductor substrate, and a second branch including a second Zener diode formed in a surface layer of the semiconductor substrate and a third diode comprising a polysilicon layer deposited on an insulating film over said semiconductor substrate, said third diode being connected in series with said second Zener diode in a reverse direction, said first and second branches being connected in parallel with each other.