Title :
Frequency-modulation-type MI sensor using amorphous wire and CMOS inverter multivibrator
Author :
Cai, C.M. ; Usami, K. ; Hayashi, M. ; Mohri, K.
Author_Institution :
Graduate Sch. of Eng., Nagoya Univ., Japan
Abstract :
A new frequency-modulation-type magnetoimpedance (MI) sensor using amorphous wire and a complimentary metal-oxide-semiconductor (CMOS) multivibrator is presented. The normal switching mode (mode I) with the alternative saturation and off states in the p-MOSFET and n-MOSFET maintains a stable multivibrator oscillation and simultaneous CMOS unsaturation state mode (mode II) generates a sensitive MI effect. A 50%/Oe change in the oscillation frequency versus external dc magnetic field was obtained. A linear sensor characteristic is obtained using a negative feedback through a frequency-voltage converter.
Keywords :
CMOS analogue integrated circuits; impedance convertors; magnetic sensors; microsensors; modulators; multivibrators; CMOS inverter multivibrator; CMOS multivibrator; CMOS unsaturation state mode; amorphous wire; complimentary metal-oxide-semiconductor multivibrator; dc magnetic field; frequency modulation; frequency-modulation-type MI sensor; frequency-modulation-type magnetoimpedance sensor; frequency-voltage converter; linear sensor; magnetic sensor; magnetoimpedance effect; multivibrator oscillation; n-MOSFET; negative feedback; oscillation frequency; p-MOSFET; switching mode; Amorphous magnetic materials; Amorphous materials; Frequency; Inverters; MOSFET circuits; Magnetic fields; Magnetic sensors; Saturation magnetization; Sensor phenomena and characterization; Wire;
Journal_Title :
Magnetics, IEEE Transactions on
DOI :
10.1109/TMAG.2003.816768
