Patent ID: 7520170

Claim:
A sensor unit with a temperature compensation circuit for connection to an accelerometer in which the accelerometer detects a plurality of acceleration values respectively for a plurality of axis directions, wherein the plurality of acceleration values have a temperature dependency, the sensor unit comprising: an input capacitor, connected to the accelerometer, for sequentially holding the plurality of acceleration values; a correction value generation circuit that sequentially generates a plurality of correction values for respectively correcting the plurality of acceleration values, wherein each of the plurality of correction values is a temperature coefficient value for correcting the temperature dependency; and a correction circuit connected to the correction value generation circuit, wherein the correction circuit receives the plurality of correction values from the correction value generation circuit and sequentially corrects the plurality of acceleration values with the plurality of correction values to generate a plurality of corrected acceleration values, and wherein the correction circuit includes: a plurality of switched capacitor circuits, connected to the input capacitor and the correction value generation circuit, for respectively holding the plurality of correction values; and a plurality of operational amplifiers connected to the plurality of switched capacitor circuits respectively, wherein the operational amplifiers each receive one of the plurality of acceleration values from the input capacitor via a corresponding one of the plurality of switched capacitor circuits to correct the received acceleration value with the correction value held by the corresponding switched capacitor circuit.