WO2025019372A1 - Magnetic field sensing at dc and high frequencies simultaneously - Google Patents

Abstract

A broadband readout interface for Hall-effect sensors is presented. This current sensing system includes two high-bandwidth Hall sensors and a fast readout interface having two signal paths, one being a high frequency path and the other being a DC/low frequency path. In one example, the readout interface (ROT) utilizes a 2-way current spinning technique in the DC/low frequency signal path to minimize offset at DC while using high pass filtering in the high frequency signal path to eliminate any offset at the high frequencies. The DC/low frequency signal path measures the Hall voltage from its Hall sensor, while the high frequency signal path can measure the inductive voltage (or an AC Hall voltage) from its Hall sensor.

Description

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seeceornmnea-eaecresueennscoro.aen.,aane caurren o e measuremen. n cases were -eec reuenc s e a-eec sen secon sna s a con onn newor can a, e secon sna reuenc s so a erncue a comensan eween e secon a es no ne reuenc s am er . sensor an e summn eae exame nroucon orresaon-eneco senesorrsaarsemanec e sensors. roorona o e ma n, e enerae a voae a caons raneromnec e's sren . er consumers.a-eec senesoarusoamroeveemnosusrrevaormar mane sensors w ~ mare saren . en currennesoensne.mosencocmumrornenusesoow esesensorss creaes a manec s rou a conucor, as a cur e aroun . ea-eec sensor sensorsren own nse wen ase. en e manec eacecocnocseesowe curerena-ene,ece seenxsoerrna nerna curren an orenzorcee ’s across e ooseermn neraes aoena ea-eec sna orasa o-eeec senvsoor.ae.ss cae s eesenasor-’eec sensorsave anneren ose, wc rese s ouu wen no exerna manec e s racnc.a s oeuou sou e ea zero,u e wen uu voaeresen n zero manec ose.aroeus sesnsuoressavaesee,enscocnauceeaon-meuece - soaweevsera,n sezoessoe maeseeevowcesorosommeeavecesose. or oers,u awas exss.ence nees an comensaene reaounerace . soe uonee oueu o, wae-eec sensor na eens caeorze as eeer s curren or voae. s ca r curren-moe or voae-moe.noer eeecorzaonsase on weere ouus a, sensnv ceran curreneves, reurn anao an accurac, wen man a caons,e nsoma oeurwuasnraee orureu.osr eeascreoroemse ceaeaor-ees,ec neunsor,ee mos crcaesn sene so na,ae-ae-eece ocsoe.or surose, searaeromea-eecse voae neesoe commercaecnueor sna. common use snnnecnue. secsurosese curren . omesers sae o e oseo caonwcenaeoncurercen snnn sae, varousnamc coer sa zaon,nues cane emoe,ncun oerecn auo-zeron,rac-an-o, an var ues.sn ese canceaonecnues, a sue o esns cane seenne eraure.ne wc uses same ano crcuroremouaon, crccurroveasn aacoer s.ensnoveersesnanuusesmoarneacoom-ex osea ecrornovresr,erosrmnsacwomexeesanca cooonsoonoaon-ow ssmemc.urrneen s unsnesna n ro ,nan, rewucresanesernnau osreec come-nrseasoounoonre.oneoraeronsamuamaeeerssanno aevresra - saoreuusoenworrecourcrenareesouuaeosasme,nweroeour ases suracon o ose. a ese s,reu mroser ewec cuves e coer sa zaon n comnaon w surrencesnnn. s canrove sens v reucn nenren oow cer nose w e eecve we.oweve ses o e oeraona am ers as sna, anr o,neee co n as swcn nosen e emouaon cocnueo reuce a so emnae rao u reors. smroves e sna-o-nose as e ouu. ves a mouae a-eec sna ssem’nsamc ose canceaon scemesn s m e e anw , so oer aroacesaveeen use a cu rreuences.ne -reuenc ecnues a orren snnn meo oowe ree r e reucon aonsnsea o aowass er. s aowsu ssem snwa co, a ou reures a com cae mu ex noe n onn ssem,ncun aa converers. coerr mseaozaa roves anw s comnn uses sam n e on w rac an o comaraors. ers.noecnueso emnae ose raer an a s o r wor consers an-a-eec sensor erencreoona sae an uses a erena- us curren eeac am er. s sensor avos on saee cusrr sesen nseomr.s s wonwnevneer,,aocw earnn m onnu as,er w uasc ceca reoru oa rrnwoona- rearc ece sensor an e enre crcur es .neecnue recen eveoe aowe aeon w o ea-eec sna rom ose w ou us searaon snnn u cou on wor or manec n curren canno eec e sna. er -anwes seannsn - oanomnasneeonreesxsoarevarousoer sensors, suc as cos sensors. nceransucers,nsea o a-eec snnons oo eerens maeneoeneweeanoveeua-ze curren an ea-eec sna.oown ae seec ose ecnuesocus onmrovn sen , some w e oersocus onecre s v or near , s me wor or asn e resua ose. ere eec senso anw mrovemen o sora- onncreasnrs.eeanw arceercourrmeanoceos weorcrcocuses usn-awnow snaaa-es.ecs senso,rsw,ernescuomsnenawu an curren eecon ssem. s ssem ca as an we-ana evces suc neesne usn nrea um nre a asaaumornuma um arsenea um arsene a aumnuma um evces. sas a-eec ,eocoowne coveerscrceuarcs ecure o eesne econ . e smuaoncemac an seasn econ . e meas resus areresene n arcae a uremen resus o eesne an an senso caon-sec cnerae crcu soesow resn are scusse necon . s ar ensn coemcaronn.e resus w e sae-o-e- eaou nerace arc ecure eneraae-aecoercresseonnsornsoeuecu mvaoneac es an carrn conucor e. nce a curren- ese manec sensorrosuccaensaemeacneeccurerenarouonwn, - rroovue a cmoannucor.onvenona a-eec sensors anw ec e sens v u me sensors.a e sae-o-e-ar a a a-eec sensors cavneaanw o reaer an z.uc varaons.uuse use oeec as manec e nnera eo er mnaure sze, e cane use enev e ower a caonsoeec currens. owner eres an aru ucuaonn e curren eec aroura acconanuceoarn,reesseonau-ececesceanussorscan eres causaenw cu.rreanasruo e o evc cuacoansu craennuse- aovwer or suc a scenaro, e crcu rean e oe. e sensor mus asoave a ssema sna rom varousesn maons, e comme nw .ueo reaou nerace crcuso nrocar avaae anw . s ves rseo e nee orovane crcu seansocrasnweuosue wm snuce s-saenmwanwa.-eec e curr.en sseonwssneneorcacaram o e arc ecure o wor. e overa sna se cvrceu esne n s eow-reuenc a maes us nowo sna as. ecnueo searae ea e o e curren snnn eec voae. ssoow-eeec a ose rom ea- e coer sa zaonecnueo mo e verson o mouae a-eec voae an remorocess e ose. e secon a o sesnveseea-e-ec raeuenc a. s uses a -ass ero remove e a- o-eeeecc ovoseaea.neeow-reuenc comonens o e c nce on e -reuenc amo.nenss awrae,roocesseeasnnaaowaesoareassevon os ossnea - avno caone.annaceerena,narseumumenncamoronerosuesa-eec esewo snaso oan e na a-eeeco voaae. e aeeovson o e sna nowoassoneo ose.a am-ee e sna an e cen remove e enerae eca o-eseecsresen n e sna srucura msma evces,ueo unavoae as ces. varesrom oneevceo anoer m we as w emeraure.ence sna con onn seensoosmus e a e o e ouu enerae e rmeemovr oeo r usesemoove nsee.s o owe-cs rue err. ueenwo nc s me anno .ns a ower ece ven use r,ueos e eecnue ms e usaeanw an ence scanno s aa ee on -reuenc snas. mar, ern u aso ree -reuenc a o remove e ose, canno e useecnseeowo-w-rereueunecncacom.onensse aanseonce use o wo sna as w e os wo eren meosor reeuenccancreanae.on,oe aeorocess a wer ecneueso,w-narmeeuenccurrean ssnancnomanaon o wo sa zaon . s n coer a a sna con onn meo e worsn ereuenc oman. rs mouaes e amsrec sanoan,oneaoera-roenauenacm carrerero.seeneursnae oosee ssnaao aws-wreeueanscansnacaenrnooesse.no nouereree weneeesre mouae sna. eesre sna s o mouae o s or na orm, wereas snce e essemoausoaeas.sesow-raosus eerenmoueanroenmosvwescees, - mrouoaee oosese asanwe acsearnnonoses.e.nceswa, es memene usn u - erena sn ecnues ac aes e reecon o com a roaaon, nose. mon-moe an envronmena su e a on o curren snnn o secnue reaecesoee moau-aeoenc soecnsoor. e,causrrsenowsnnn e curren snnn ara wors sm nn .. mouaon oc, suc a mouaesare o e eec voae. ou n a ono a,esr ae a- searaes ea-eec ose eavn unmosouae. cemac o e reaou nerace eoe crrcu scemac o e s sownn .. ranc sance s-ereouwe-ncreuaenc.aa-,e wece senesoroom connece o eo ranc rou e curr s oc, wc s eaorae n .. en snnn _an ere arewo ases conroe coc snas o e_.a_en- _{s ,urn ase,ermnas an} curren, w eeeercmnsaenssoraanrecoanrneeccoenneo e as _ous_ue _o, e_sconn_oe_cc_. ce o e a on_es_xo_{, we}e_nermn_sas sw_,c_urn a e as curren s nowrove oe u suc w e e ouu saenromerm rmnas an , e swcn rom ase o asenas an .ueo measure a-eec voae c , eoar o e nce e ose sueo anesn ewo ases. en measu srucura msmaces an s remans unareeceeweenweo swermcnans.ns aoresuas,esa, - mosuaeesameaas-eeecco vcoareeuesnce,nerae, wosereuenc ose remans aow-reuenc scraene ea s-nea.ec ranscoenruecsanoceamecrceurs canncue oeraona . or sne-ene . cnonuuraonerena saeoro ese sesne usn es.oee-rs caescoe con uraon. s e o uses casco avsccoesecoorn uraaonnsa,noe-ca e c anscwoe.roomare o oer swn w ou comromsn onan o ves aare resusn ouu common-moe rranw . s oe-cascoe con uraon asorane . e su reecon rao . oves a ower reureesn aecsommnonn-moau erena . , sae, snce a eeeac saeo suor eac an e common- s erena ouus. eurose o aroraemo ceeeac crcu so esa s an correc ouuurr ceonmmonn-meoacevoranacewo eomaonuaunnno e s saeeuces e ouu common-moe es. averan ewo ouu noes an en covoae e reerence common-moe v mares w eneraes e reure conoae .s a resu, source o eoe- ro voaeor e curren a as curr cascoe sae. us, conro n coseo enrou eesseee oaucuooco.mmon-moe voae s e nex sae o eu eren eean oerenea. amnceer.s ssa seaaea sounreeesroncr. aeases erena ouus, a smar common-mo ve s reure or san sae as we.eeeac sae - 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ss er a.urn esn,o ese reuenc sna sameo aceve a consan nar oeuueunc.eswserereeuences - caz.eee crcorsoss-soovveerrrreeuueenncc wsccososerve oe . aecaeess an e snnn senoe aroxmae snnn reuenc s e cen rereuenc, so a e reuenc a.o ers areesece rom eow- ressor an caacor vaues ne w e same e a smoo crosso o mac ereuences an comonens’oe ver.o mnmze e eec o er ressor an caraacnceoroneewcrosss-omverarrveauueenc, esame orer are use. eaou o eevces s an er o mnmze erocess varaon. s aso o mze rse me o o sna ass ~s sso.wnenn., e rom e summn am er cane seen as a ouu o snas, vn aas use reso a comnaon o nvern con uraons use or nse. nce an snverse wen comare e summn am er, as owever, sn asoewe sneanruom. ewo anonsern ean, e -reuenc a as a o ~ o ~.en.ce ae eow-reuenc a as aan e we e summn aamn oer.o esrove rou sna, w e eow-reuenc sna s-reuenc o . ss were e- an varaae w coamesan n., e, -reuenc an cane seece usn - s resec avn , as sownn .. ese srove a se n esa.n onca.se,o., an . . eeau eween ewo sna a ass,n can an msmac eenn uon weer s reeures or cane use ncrease ean o e -reuencoaecr.ease or ou e anass waserorme on e o o e smuuaaonn wasreorvormne aoxees neuc vrocuae.eroonrmeancaero - acsro~ssem.eraeusreananarroecvesascorners. eaceve an e ressors an eransson o eans . m. emeraure coe c ors a ave anneren roorona o asen. e crcu esn u zes a com menar o aosouueemeraure an ressorsn c eemeraure comnaon o e ose-oo am er con uraons across os cavenano mnaenaavneeemearanucroenscoaen. econsecuve eac oer’s eec,een cens cance ou rouou e rane. ean varaons mnmum w mu ea-eece reaou neracesesne sn a e con sensorsn mn.ence, ean ereuenc caa san o overereemaeoruaucrer,cuoaesmosnsowrnae .. nce eac sensor maera w ave e n emeraureeenen sens v es, e a ren cose-oo ressors use or mnmzn en an overemeraure wou e mo e canen emeraure eec o eanrownc.uar seno nu e eenences measure or sor, once a easuremen resus a eaou neraceesn z.e su s veoseae oro.v n a suare wavenu o a_{n ar} an o . s use. z. ree_{erove a com menar coc sna o} sn ouus are oserve, eow-reuenc ouau ,. -reuenc sna , an na summe n .. e reesumeassuarreenoosrcmaozsecoeoreseursouaresown ow-reuenc a ouu s a suare sna n. e sow rsn ee, w e e -reuenc au owuu a - snaes oauue ese,en avnas a-rmuscnssoruaerrrse me. e am e verson o enu w a e wave. s e nosen e sna s ran as resonse. e snce om noserom e envronmen ow e am ers are anw , an eres no an-wass. ern n e -reuenc a o m ou o see eerormance o o eas an na e suee,noneao reseesesucszoowme ansar..usere, can ecas sow. , on e oeran, e an en me. ea-me o an e rsas aoner rse e same een e- re e-me o were se eua o e crossov uences o o ers ea-m erreuenc. s rse-me o an ,nureor are ~ s. e na summe ouu rov n n, sows e a on o ewo snas, sn aas resonseo enu use. ewo neua,s, n wuc an sneaa.s,o areenvneareouasucomeanren-oasee w eaou neraceesn w a-eec sensor s essens vneerwe mueereormaanc-eeo e crcu. mn, an ence cane u ec sensorsn ermna a-eec se oresn w an our sensor sou evce.reera a anw caa o e csosen.o eecsesnesno e anw were asasa-e srosrsu.se or eseess w eea.-eeesce asreensowrsarewre-one on e e nex o eac oer. oeseanrseorcsonnaecrecaeo one esaasme - scownn . an ..ne sensors connece o e suercren snnn o eow-reuenc a, w e e secoonn sseennssoorrsoecsonnnoecneeeoanecurren-rseunennc a. e son o e -reu n snce r enc a, an sa oes no oocess an sna curren snnn s on reure erow-reuenc snas.ence swo aernan wrmnas an are connece o e curren as, nueoe oeer.wo cermnas an are use or sensors a a urren racesarcae nex o e s us sance o . mm. curren useeneraor -ecurorve e curren race on e an rove concenrraenorusesoresn. manec e erre coresa acesounse n sesn. s aae assesrom s m e suc a wa a e curren race es concenrae,e an e sensors s nse ea. an mrove sens v manec e ono e sensors erre, wc as . e mos common maera use s neee or ese mane ermea an owosses as manec e concen c e concenraors. ou e ssem an e ss raors no a necessar ar o e esncrease sensem canememene w ou , reucn e nose cavure ocuessnensore. e an .eae-eesenc csoennsorsonasreo ase w a curren o same ma e are se u n e c nner as exane n erevous susecon. e cu rur err sreen on u nseoorseeen e se cer ona msoorr neoro seeuc ueecs o.sor esu seenns see ors ra o aensa se nerace crcu. e normaze esn resus ae n .. e curren waveormeas a ~ are sown ecas s or euseuraon. eow-nreueennc - ausess.nae sow-r resueesncanaensonaowsvese acusrraernea uurne oveerrasnreseoneseoo eecusrrsenem.ussem,enwocn sees revous secon, e -reuenc sna a e n e n am ue an w sower w e ae w a eran usn e seensev summon am er.rom s ure, e . m . e sensor cane cacuae as m = ncuee souu nsosnas o e sensn ssemn . sueo ee eeas a eac curren use ee. s ssem an cercoumrarennecucsoeuenneraeorw.eeneseensoenssen cane emnae usn soaonn e senso eas caocnnaecne.oocaecua,eue noremsanueacosee,ser esneensors no rov n an curren uses on e cur rae canen e vaue o eow-re ren race. e s noe. enu-reerre resuenc ouu o e m. s ose srom e sensorueuao ose s. curren snnn ecnue. s can usn a-wa usn a-wa or-wa snnn ee mnmze urer wor, e reaou nerace was cnue.or s sames, an a. m averae oessee wawsmeamsuure.e sensor a snee nourmsaezsesroesonseo e sensor w e o nvere w resecwnone c.urr. an are summe ouu s ease rnesounsse. e na own rou e curren race a eo e curren s e comnaon o , wcnosowns aesecw . useu w aoner rse me, an , wcurraen sar rsn ee an ence maes e na ouu saa rom s ure, cane seen a eow an s-er. - ~reuesn.cavas, resecve,ave a rse an a me o same ernre sumencaresresonse messueoavn e revous . s ensuresnroeerr sesnanas scusse n .rom . , e r a on, resu n sna can se me o e -reuenc anw oe noeecurarsen snesn.snsrse me caes e reson. ssem an owas can rse emree.arneemwomeosoranw cacuaonrom ar eo u ze n ersso use an meo.xmnaooenrmoecaocusaeanw , ven as. rse resonseoe eanwonv.eror aeccrurse me o e se sae-o-e-ar, e secon meo s uasee.comearson w anw or s wor s z. cacuae omarsono sae o e ar s sow cnomnarasoneo. eereesevnaw e sae-o-e-ar eec sensorssncue nne woareu.sne onocusa- wor wasomrove eanw o s overa curre o e an ence e s wor acnev seesnsne sseesm.s seenrom eae, a- reuenc comare o oer _^ ^{eec sensor-ase esns.}

- ae:omarson w sae-o-e-ar s wor rocess ._m ^{. m} .m .m . ^{. m anw z z} _z > _m z _.z ^z . m ens v - _mm ^{- - -} m.m* emeraure – o - rane ° - - - o – o ° ° esua > . m se > m .m m m. . ** *o conver rom m o mm, eormuaor manec e creae curren n a sra wres use

were = sren o manec e, ^^

e wre. w =ermea cerom re, an = *u*seo.conver rom o m, e reore sens v s oncusons a-eee ccurrseennssensn ssem o s wor maes use o anw sorsesanneareoaroua-neerecacesensor.s, a - remmovesneanowse. an aamsaesse sna wou useor sesn owever,as-eec casnenseorsare aonnouar-eermencaseanso-resweccsensors. s sse umseuorzes ea maes mnaurzaon muc maser as comareo oerevces. ss a non-nvasve ronvecn aease reecsoonnsessem. as a anw , e usenower eecrono a currenuse, anence can conro an oversoo saecs assecmas.ons,ncun

Claims

- .n eecrca crcu comrsn: arsa-eec sensor eemen a secona-eec sensor eemen rece avearsr ssnsaenscoornsnoannronmewoer crosnureo sensor ecemceunoan a-eec reuen rerouvencears snaavn a rseeceaveseacosnecosnnsaenscoorn ₁ snoannro nmewoerseccoonnuare-eoec rnesourenecemceunoanrerouvenceasecon snaavn aow sna a saunmmneasmeconesrcnoan₂ anureco receveers sum ouu a onureorove a e secon snasmees arssecsonnaanmes arsanus seec weeresuncear asreaun an e seconan are s susana aeweenecn zreersoonrseeo e sum ouu reuenc_s o e secona-eec sueennscor.an acuo r.esoenseeeocrca crcu o cam, werenereuenc areuenc raenseumeouweeun vaarnes. n_s.omorean over .₁-₂e e<ec.rc₁a. crcu o cam, weren - s.nae ecoecrca crcu o cam, wereners crcu nomonane naeworosnecusesnaa.curren snnn s.nae ecoencrc noa cnrncr cu nceuwooo cam, wereners sa zao rmncauee as a cooseer sna. s.nae ecoencrcoanncrnceuworo cncaumes,awerenasse secoenr. s.econeeaec-recaeccsrecnusorsoacveame,sawmeereevncers an conuraon. e s.ensoeresecnarcasacracu-eoeccasmna,. wereners s.ensoeresecnarcasacnrcnuucovecsamna,.werene secon se.nsoreseencarcsaacrrecuuencoscame,a we-reenece s sencaon. r.eueenceecrca crcu o cam, werene eermne s aereaue-eec snaas areuenc s secona-eec sennscor.o ana e currenoe