Patent ID: 7271599

Claim:
A semiconductor apparatus comprising: a plurality of resistance measurement elements, each converting a physical quantity into a resistance value; a first switch device connected to one of said resistance measurement elements to permit electrical current to pass through said resistance measurement element; a bias circuit that applies a bias voltage to one of said resistance measurement elements; and an integrating circuit that integrates a current flowing through one of said resistance measurement elements to store the integrated current; said semiconductor apparatus detecting changes in a resistance value of one of said resistance measurement elements, based on the current stored in said integrating circuit, thereby indirectly measuring said physical quantity; wherein said bias circuit includes; an OP amplifier, having a non-inverting input terminal connected to a bias voltage supplying terminal; a MOS transistor, having a gate connected to an output terminal of said OP amplifier and having a source connected to an inverting input terminal of said OP amplifier and connected via said first switch device to one of said resistance measurement elements; and a second switch device connected between the gate and the source of said MOS transistor; and wherein there is provided a switch control circuit that performs control so that, when a resistance measurement element, the resistance value of which is outside a preset range, is selected, said first switch device is opened and said second switch device is short-circuited.