Patent ID: 6417678
Filing Date: 2002-07-09
Classification: G01R

Abstract:
A bridge circuit comprising:a wheatstone bridge consisting of a first resistor group and a second resistor group connected in parallel between a first junction point and a second junction point, said first resistor group consisting of a first resistor and a second resistor connected in series with the third junction point therebetween, said second resistor group consisting of a third resistor and a fourth resistor connected in series with a fourth junction point therebetween; a first voltage measuring means for measuring and outputting &Dgr;V representing a voltage difference between said first junction point and said second junction point; a second voltage measuring means for measuring and outputting V10 which represents a voltage difference between said third junction point and said fourth junction which are diagonal junction points of said wheatstone bridge; a calculating means for calculating from said V10 a correction value by which said &Dgr;V must be changes for drift correction corresponding to a change is an environmental condition; and a constant current circuit which is connected to said third junction point and serves to cause a constant current to pass through said wheatstone bridge.