Input protection resistor used in input protection circuit

An input protection circuit for protecting a protected circuit from voltage surges in a signal at an input pad, said input protection circuit comprising:

• an input protection resistor comprising a first region of a second conductivity type in a semiconductor body of a first conductivity type and a second region of the second conductivity type surrounded by said first region, said second region having an impurity concentration higher than an impurity concentration of said first region;
• a first wiring layer coupling said input pad and said second region;
• a second wiring layer coupled to said second region at a position spaced from said first wiring layer and coupling said second region to an input stage of said protected circuit;
• and
• an input protection element coupled between said second wiring layer and one of a ground terminal and a power source.

A semiconductor device, comprising:

• a semiconductor body of a first conductivity type;
• an integrated circuit on said semiconductor body;
• an input pad coupled to aid integrated circuit for receiving input signals;
• and
• an input protection circuit coupled to said input pad and said integrated circuit for protecting said integrated circuit from voltage surges in the input signals, said protection circuit
• an input protection resistor comprising a first region of a second conductivity type in said semiconductor body and a second region of the second conductivity type surrounded by said first region, said second region having an impurity concentration higher than an impurity concentration of said first region;
• a first wiring layer coupling said input pad and said second region;
• a second wiring layer coupled to said second region at a position spaced from said first wiring layer and coupling said second region to an input stage of said integrated circuit;
• and
• an input protection element coupled between said second wiring layer and one of a ground terminal and a power source.