Semiconductor device

A semiconductor device comprising a sensor which converts a measured physical quantity to an electric signal and outputs the signal, which has a peculiar temperature coefficient,

• amplifying means which receives a sensor output signal of said sensor, amplifies the sensor output signal at a required amplification factor of temperature independence, and cancels an offset,
• reference signal producing means for producing a reference signal varying at a temperature coefficient equal to that of the sensor output signal of said sensor,
• comparing means for comparing a magnitude of the amplification output signal from said amplifying means with a magnitude of the reference signal from said reference signal producing means and for outputting a required signal according to a comparison result, and
• constant voltage generating means for generating temperature-independent constant voltage to be supplied to said sensor,
• characterized in that said amplifying means, said reference signal producing means, said comparing means, and said constant voltage generating means are formed using a semiconductor layer provided on an insulating substrate.