Semiconductor stress sensor

摘要

A semiconductor stress sensor includes a field-effect transistor for producing a drain current commensurate with a stress applied thereto. The gate of the field-effect transistor is supplied with a gate bias voltage from a gate bias voltage generator. The drain current from the field-effect transistor is converted into a detected output signal by a current-to-voltage converter. The gate-to-source voltage of the field-effect transistor can be varied to reduce the drain current in a standby mode when no stress is to be detected. To vary the gate-to-source voltage, the gate bias voltage applied to the gate of the field-effect transistor may be slightly varied or the source potential thereof may be slightly varied. The gate-to-source voltage of the field-effect transistor slightly differ from each other in the standby and stress sensing modes. Even in the standby mode, the field-effect transistor is supplied with substantially the same voltage as in the stress sensing mode. When the semiconductor stress sensor switches from the standby mode to the stress sensing mode, the drain current is subjected to an only small drift, allowing the semiconductor stress sensor to produce a highly accurate, stable detected output signal within a short period of time.