MAGNETORESISTIVE TRANSDUCER Russian patent published in 1999 - IPC

FIELD: automatic control; tachometers, displacement transducers, DC and ac magnetic field meters. SUBSTANCE: transducer using bridge circuit arrangement has four thin-film double-layer magnetoresistive strips unidirectionally oriented from start to finish. Strips are interconnected through conductors as follows: starts of first and fourth strips, finishes of second and third ones, finish of first strip to start of third one, and start of second strip to finish of fourth one. Additional insulating layer covers bridge circuit and carries control conductor running sequentially above first and second strips from start to finish and above third and fourth strips from finish to start. Passing current through control conductor builds up magnetizing vectors in strips in such way that external magnetic field being recorded finally increases resistance in one pair of strips and reduces it in other pair. In case of reversal of external magnetic field resistance in pairs of strips changes in reverse manner. Such change in resistance causes varying-polarity potential across diagonally opposite terminals of measuring bridge. To ensure above-described behavior of transducer in magnetic field as well as to reduce hysteresis, strips have unidirectional low-magnetization axis oriented lengthwise of strips. EFFECT: enlarged linear section and reduced hysteresis of odd voltage-oersted characteristic that does not require DC bias. 1 cl, 4 dwg