Sensitive and quick response micro magnetic sensor utilizing magneto-impedance in Co-rich amorphous wires

Author

Mohri, K. ; Panina, I.V. ; Uchiyama, T. ; Bushida, K. ; Noda, M.

Author_Institution

Dept. of Electr. Eng., Nagoya Univ., Japan

Volume

31

Issue

2

fYear

1995

fDate

3/1/1995 12:00:00 AM

Firstpage

1266

Lastpage

1275

Abstract

New high performance micro magnetic heads and sensors are presented utilizing the giant magneto-impedance (GMI) in the Co-rich amorphous wire. Typical performances or advantageous features of the head and sensor-are as follows; (i) head size can be reduced to about 1 mm maintaining a flux detection sensitivity of about 10/sup -5/ Oe, (ii) a rapid response with the cut-off frequency of 20/spl sim/30 MHz using a wire current of 200/spl sim/300 MHz, (iii) high temperature stability of about 0.01 %FSspl deg/C with a maximum operating temperature of about 180/spl deg/C using a negative feedback loop in the sensor circuit, and (iv) small power consumption of less than 10 mW using a self-oscillation circuit, in which a MI element voltage decreases to zero (100% change) with an external field of about 2 Oe. The basic properties and mechanism of the GMI, the head construction, the sensor construction principle, sensor circuits and sensing applications are discussed.<>

Keywords

amorphous magnetic materials; boron alloys; cobalt alloys; ferromagnetic materials; giant magnetoresistance; iron alloys; magnetic heads; magnetic sensors; silicon alloys; 180 degC; 20 to 30 MHz; Co-rich amorphous wires; FeCoSiB; cut-off frequency; flux detection sensitivity; giant magnetoimpedance; head construction; head size; magnetic heads; micro magnetic sensor; negative feedback loop; power consumption; self-oscillation circuit; sensor circuits; temperature stability; wire current; Amorphous magnetic materials; Amorphous materials; Cutoff frequency; Feedback circuits; Magnetic flux; Magnetic heads; Magnetic sensors; Sensor phenomena and characterization; Temperature sensors; Wire;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/20.364817

Filename

364817