Abstract
Micro-electromechanical system (MEMS) magnetic sensors are widely used in the nanosatellites field. We proposed a novel high-precision miniaturized three-axis digital tunneling magnetic resistance-type (TMR) sensor. The design of the three-axis digital magnetic sensor includes a low-noise sensitive element and high-performance interface circuit. The TMR sensor element can achieve a background noise of 150 pT/Hz1/2 by the vertical modulation film at a modulation frequency of 5 kHz. The interface circuit is mainly composed of an analog front-end current feedback instrumentation amplifier (CFIA) with chopper structure and a fully differential 4th-order Sigma-Delta (ΣΔ) analog to digital converter (ADC). The low-frequency 1/f noise of the TMR magnetic sensor are reduced by the input-stage and system-stage chopper. The dynamic element matching (DEM) is applied to average out the mismatch between the input and feedback transconductor so as to improve the gain accuracy and gain drift. The digital output is achieved by a switched-capacitor ΣΔ ADC. The interface circuit is implemented by a 0.35 μm CMOS technology. The performance test of the TMR magnetic sensor system shows that: at a 5 V operating voltage, the sensor can achieve a power consumption of 120 mW, a full scale of ±1 Guass, a bias error of 0.01% full scale (FS), a nonlinearity of x-axis 0.13% FS, y-axis 0.11% FS, z-axis 0.15% FS and a noise density of x-axis 250 pT/Hz1/2 (at 1 Hz), y-axis 240 pT/Hz1/2 (at 1 Hz), z-axis 250 pT/Hz1/2 (at 1 Hz), respectively. This work has a less power consumption, a smaller size, and higher resolution than other miniaturized magnetometers by comparison.
Highlights
The earth is a huge magnetic source and scatters around the weak magnetic field
There is a specific relationship between the size, direction of the magnetic field, and geographical position
Materials The tunneling magneto-resistance sensor element with the multilaminar structure is from
Summary
The earth is a huge magnetic source and scatters around the weak magnetic field (about 50 μT). We can achieve the high-precision GPS navigation by obtaining accurate geomagnetic field information. It is strategic and tactical for concealed combat equipment (such as submarines, stealth aircraft, etc.) [1]. If we can accurately measure the anomaly magnetic field, we can get the location, size, and other information of the target object [2]. TThhee hhiigghh--pprreecciissiioonn mmiinniiaattuurriizzeedd mmaaggnneettoommeetteerr iinn mmiilliittaarryy aanndd cciivviilliiaann fifieelldd. MMiinniiaattuurriizzaattiioonn hhiigghh--ppeerrffoorrmmaannccee mmaaggnneettoommeetteerrss bbaasseedd oonn AAMMRR ((aanniissoottrrooppiicc mmaaggnneettiicc rreessiissttaannccee)),, GGMMRR ((ggiiaanntt mmaaggnneettiicc rreessiissttaannccee)),, aanndd TTMMRR ((ttuunnnneelliinngg mmaaggnneettiicc rreessiissttaannccee)) aarree wwiiddeellyy uusseedd iinn mmiilliittaarryy aanndd cciivviilliiaann fifieelldd. TTMMRR bbaasseedd oonn ttuunnnneelliinngg ccuurrrreenntt hhaass aa llaaggeerr cchhaannggee rraattee ooff mmaaggnneettoo--rreessiissttaannccee ccoommppaarreedd wwiitthh GGMMRR aanndd AAMMRR. TThhee ttuunnnneelliinngg mmaaggnneettoo--rreessiissttaannccee sseennssoorr eelleemmeenntt,, ccuurrrreenntt ffeeeeddbbaacckk iinnssttrruummeennttaattiioonn aammpplliififieerr wwiitthh cchhooppppeerr tteecchhnniiqquuee,, SSiiggmmaa--DDeellttaa mmoodduullaattoorr aanndd ddiiggiittaall ddeecciimmaattiioonn fifilltteerr aarree iinnttrroodduucceedd aanndd ddeessiiggnneedd iinn SSeeccttiioonn 22. TThhee ppeerrffoorrmmaannccee ccaann bbee iimmpprroovveedd bbyy cchhooppppeerr tteecchhnniiqquuee,, ooffffsseett rreedduuccttiioonn lloooopp tteecchhnniiqquuee,, aanndd ddyynnaammiicceelleemmeennttmmaatctchhiningg. .TThehepeprefrofromrmanacnecpeapraarmaemteertserosf oAfSAICSIaCreatreestteedstebdy bthyetheexpeexrpimereimntesn. tFs.inFailnlya,llSy,ecSteioctnio4n 4cocnocnluclduedsesthtehesstutuddyy ooff MMEEMMSS//TTMMRR tthhrreeee--aaxxiiss iinntteeggrraatteedd mmaaggnneettoommeetteerr pprroottoottyyppeeananddtetsetisntigngresruesltusl,tws, hwichhicshhoswhsowthsatththaet ptherefopremrfaonrcmeaonfcme ionfiamtuirniziaetdurTiMzeRd dTiMgiRtadl migiatganl emtoamgneetteormhaestegrrheaast agdrevaatnatadgveasnitnagthese ianptphleicaaptipolnicoaftinoannoof-snaatneloli-tseatfieelllidte. field
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
