PURPOSE: To make a transistor input part strong to surge breakdown, electrostatic breakdown, etc. by changing a protection diode into a resistor type and then extending a wiring to an input protection resistor pattern.

CONSTITUTION: An N+ diffused layer 51 of the protection diode 2 is used as a resistor between the wirings 41 and 42. Here, the resistance value of a poly Si resistance layer 1 is 1.5kΩ or less. The resistance value of the layer 51 is 1/10 or less of that of the layer 1. Further, a gate insulation film thickness of an MOSFET whereto the resistor 51 is connected is at 800 or less. The influence by the dispersion of input contact resistances can be reduced by changing the input protection diode into the resistor type in this manner. Besides, the local concentration of electric fields is prevented, and thus negative side static strength can be intensified by extending the wiring to the input resistor pattern.