Ishicilelwe ibhodi yesekethe iingxaki ezinzima kunye nezisombululo

Umbuzo: Njengoko bekutshiwo ngaphambili malunga nezichasiso ezilula, kufuneka kubekho izinto ezichasayo ezisebenza kakuhle kanye njengoko silindeleyo. Kwenzeka ntoni kwinkcaso yecandelo lecingo?
A: Imeko yahlukile. Ngokuqinisekileyo ubhekisa kwintambo okanye ibhendi eqhubayo kwibhodi yesekethe eprintiweyo esebenza njengocingo. Kuba i-superconductors yamaqondo obushushu egumbi ayikabikho, nabuphi na ubude bentsimbi busebenza njengesixhobo sokuxhathisa esisezantsi (esisebenza njenge-capacitor kunye ne-inductor), kunye nefuthe lazo kwisekethe kufuneka ithathelwe ingqalelo.
2. Q: Ukuxhathisa kwentambo yobhedu emfutshane kakhulu kwisekethi yomqondiso omncinci akufuneki kubaluleke?
A: Makhe siqwalasele i-ADC eyi-16-bit ene-impedance yokufaka eyi-5k ω. Thatha ukuba umqondiso wesiginali kwigalelo le-ADC uqukethe ibhodi yesekethe eprintiweyo (i-0.038mm ubukhulu, i-0.25mm ububanzi) ngebhanti e-10cm ubude. Inokuxhathisa malunga ne-0.18 ω kubushushu begumbi, elingaphantsi kancinci kune-5K ω × 2 × 2-16 kwaye ivelise impazamo yokufumana i-2LSB kwinqanaba elipheleleyo.
Ngokuqinisekileyo, le ngxaki inokuncitshiswa ukuba, njengoko sele kunjalo, ibhanti eqhubayo yebhodi yesekethe eprintiweyo yenziwe banzi. Kwimijikelezo ye-analog, kukhethwa ngokubanzi ukusebenzisa ibhendi ebanzi, kodwa uninzi lwabayili bePCB (kunye nabaqulunqi bePCB) bakhetha ukusebenzisa ububanzi bebhendi ubuncinci ukulungiselela ukubekwa komgca wesiginali. Ukuqukumbela, kubalulekile ukubala ukuxhathisa kwebhendi eqhubayo kunye nokuhlalutya indima yayo kuzo zonke iingxaki ezinokubakho.
3. Q: Ngaba kukho ingxaki ngokwamandla ebhendi eqhubayo enobubanzi obukhulu kakhulu kunye nocingo lwentsimbi ngasemva kwibhodi yesekethe eprintiweyo?
A: Umbuzo omncinci. Nangona i-capacitance evela kwiqela lokuqhuba lebhodi yesekethe eprintiweyo ibalulekile (nakwiziphaluka ezihamba rhoqo, ezinokuthi zivelise oscillations ophakamileyo), kufuneka ihlale iqikelelwa kuqala. Ukuba oku akunjalo, nokuba ibhendi ebanzi yokuhamba eyenza i-capacitance enkulu ayongxaki. Ukuba kuvela iingxaki, indawo encinci yenqwelomoya yomhlaba ingasuswa ukunciphisa amandla emhlabeni.
Q: Shiya lo mbuzo okomzuzwana! Yintoni inqwelo moya?
A: Ukuba ifoyile yobhedu macala onke ebhodi yesekethe eprintiweyo (okanye yonke i-interlayer yebhodi yesekethe eprintiweyo) isetyenziselwa ukuzinza, yile nto siyibiza ngokuba yindiza. Nawuphi na ucingo olucwangcisiweyo luya kucwangciswa kunye nokuchasana okuncinci kunokwenzeka kunye nokunyanzeliswa. Ukuba inkqubo isebenzisa inqwelomoya yomhlaba, kunqabile ukuba ichaphazeleke ngengxolo yomhlaba. Ukongeza, inqwelo moya eyomeleleyo ikwanomsebenzi wokukhusela nokupholisa
Umbuzo: Inqwelomoya yomhlaba ekhankanywe apha inzima kubavelisi, akunjalo?
A: Kwakukho iingxaki kwiminyaka engama-20 eyadlulayo. Namhlanje, ngenxa yokuphuculwa kwe-binder, ukumelana ne-solder kunye netekhnoloji ye-wave soldering kwiibhodi zesekethe eziprintiweyo, ukwenziwa kweenqwelomoya ezisisiseko kuye kwaba yinto yesiqhelo yeebhodi zesekethe eziprintiweyo.
Umbuzo: Uthe ukubanakho kokuveza inkqubo kwingxolo yomhlaba ngokusebenzisa inqwelomoya emhlabeni incinci kakhulu. Yintoni eshiyekileyo yengxaki yomhlaba yengxolo engenakusonjululwa?
A: Isekethe esisiseko yenkqubo yengxolo esekwe emhlabeni inenqwelomoya yomhlaba, kodwa ukuxhathisa kunye nokunyanzeliswa ayizizo zero – ukuba umthombo wangoku womelele ngokwaneleyo, uya kuchaphazela imiqondiso echanekileyo. Le ngxaki inokuncitshiswa ngokulungiselela ngokufanelekileyo iibhodi zesekethe eziprintiweyo ukuze i-current high ingahambi kwiindawo ezichaphazela umbane womhlaba weempawu ezichanekileyo. Ngamanye amaxesha ikhefu okanye ukusikwa kwindiza yasemhlabeni kungaphambukisa indawo enkulu yomhlaba kwindawo ebuthathaka, kodwa ngokunyanzelwa ukutshintsha inqwelomoya yomhlaba inokuphambukisa umqondiso kwindawo ebuthathaka, ke olo hlobo kufuneka lusetyenziswe ngononophelo.
Q: Ndilazi njani ithontsi levolthi eliveliswe kwinqwelomoya?
A: ngesiqhelo ukwehla kwamandla ombane kunokulinganiswa, kodwa ngamanye amaxesha ukubalwa kunokwenziwa ngokusekwe kwimathiriyeli kumhlaba wenqwelomoya (igama elingu-1 ikopolo lobhedu eline-045m ω / □) kunye nobude be Iqela lokuqhuba elidlula ngoku, nangona ukubalwa kunokuba nzima. Iivolthi kwi-dc ukuya kumaza asezantsi (50kHz) zinokulinganiswa ngezixhobo zesikhulisi ezinje nge-AMP02 okanye i-AD620.
Isibonelelo sokukhulisa samiselwa kwi-1000 kwaye saqhagamshelwa kwi-oscilloscope ngovakalelo lwe-5mV / div. Isikhulisi sinokubonelelwa sisuka kumthombo wamandla ofanayo nowesekethe ephantsi kovavanyo, okanye kumthombo wamandla waso. Nangona kunjalo, ukuba umhlaba wesikhulisi wahlulwe kwisiseko samandla, i-oscilloscope kufuneka iqhagamshelwe kwisiseko samandla esekethe yamandla esetyenzisiweyo.
Ukuchasana phakathi kwawo nawaphi na amanqaku amabini kwindiza esemhlabeni kunokulinganiswa ngokongeza iprobe kula manqaku mabini. Indibaniselwano yesibonelelo sokukhulisa kunye nobuthathaka be-oscilloscope yenza ukuba ubungakanani bemilinganiselo bufike kwi-5μV / div. Ingxolo evela kwisikhulisi iya kunyusa ububanzi be-wave ye-oscilloscope curve malunga ne-3μV, kodwa kusenokwenzeka ukufezekisa isisombululo malunga ne-1μV-eyaneleyo ukwahlula ingxolo yomhlaba kunye nokuzithemba okungama-80%.
Q: Yintoni ekufuneka iqatshelwe malunga nale ndlela yovavanyo ingasentla?
A: Nawuphi na umhlaba otshintshayo wemagneti uya kubangela amandla ombane kwiprobe lead, enokuvavanywa ngokusasaza okufutshane kwiinkqubo (kunye nokubonelela ngendlela yokuphambuka ekumelaneni komhlaba) kunye nokujonga ifom ye-oscilloscope. I-wave wave ye-AC ibangelwe kukungeniswa kwaye inokuncitshiswa ngokutshintsha indawo ekhokelayo okanye ngokuzama ukuphelisa amandla kazibuthe. Ukongeza, kufuneka kuqinisekiswe ukuba isiseko sesikhulisi sidityaniswe nomhlaba wenkqubo. Ukuba isandisi-lizwi sinalo olu nxibelelaniso akukho ndlela yokuphambuka ibuyayo kwaye isandisi-lizwi asizukusebenza. Isiseko somhlaba kufuneka siqinisekise ukuba indlela esetyenzisiweyo yokusombulula ayiphazamisi kulwabiwo lwangoku lwesekethe phantsi kovavanyo.
Umbuzo: Uyilinganisela njani ingxolo ephezulu yokuhamba komhlaba?
A: Kunzima ukulinganisa ingxolo yomhlaba ye-hf ngesixhobo esisebenza ngobubanzi be-bandband, ke yona i-hf kunye ne-VHF yezixhobo ezifanelekileyo zisebenza ngokufanelekileyo. Iqukethe isangqa esine-ferrite magnetic (ubukhulu obungaphandle be-6 ~ 8mm) kunye neekhoyili ezimbini ze-6 ~ 10 zijika nganye. Ukwenza ifomathi yenguqu ephezulu yokuzahlula wedwa, enye iikhoyili iqhagamshelwe kwigalelo lokuhlalutya umboniso kunye nelinye kwiprojekthi.
Indlela yovavanyo iyafana kwimeko yeefrikhwensi ezisezantsi, kodwa i-spectrum analyser isebenzisa ubude beempawu zobungakanani bamaza ukubonisa ingxolo. Ngokungafaniyo neepropathi zedomeyini yexesha, imithombo yengxolo inokuhlukaniswa ngokulula ngokusekwe kwiimpawu zabo zefrikwensi. Ukongeza, ubuntununtunu be-analyzer ye-spectrum ubuncinci yi-60dB ephezulu kunaleyo ye-broadband oscilloscope.
Q: Kuthekani ngokunyanzeliswa kwengcingo?
A: Ukunyanzeliswa kwabaqhubi kunye neebhodi ze-PCB zokuqhuba azikwazi ukungahoywa kwii-frequencies eziphezulu. Ukulungiselela ukubala ukungafakwanga ngocingo oluchanekileyo kunye neebhendi eziqhubayo, iindlela ezimbini zokulinganisa zenziwa apha.
Umzekelo, ibhendi eyi-1cm ubude kunye ne-0.25mm ububanzi iya kwenza inductance ye-10nH.
Ukuqhuba inductor = 0.0002LLN2LR-0.75 μH
Umzekelo, inductance ye-1cm ubude be-0.5mm yocingo lwangaphandle lobubanzi yi-7.26nh (2R = 0.5mm, L = 1cm)
I-band inductance = 0.0002LLN2LW + H + 0.2235W + HL + 0.5μH
Umzekelo, inductance ye-1cm ebanzi ye-0.25mm yebhodi yesekethe eprintiweyo yebhodi ye-9.59nh (H = 0.038mm, W = 0.25mm, L = 1cm).
Nangona kunjalo, ukuphendula okunganyanzelekanga kuhlala kuncinci kakhulu kune-parasitic flux kunye ne-voltage ebangelwa sisiphaluka esisikiweyo. Indawo yeluphu kufuneka incitshiswe ngenxa yokuba i-voltage ebangelwa ilingana nendawo ye-loop. Oku kulula ukuyenza xa i-wiring ijijekile.
Kwiibhodi zesekethe eziprintiweyo, iindlela ezikhokelayo kunye nezobuyayo kufuneka zisondelelane. Utshintsho oluncinci lweentambo luhlala lucutha ifuthe, jonga kumthombo A odityaniswe kumandla asezantsi e-loop B.
Ukunciphisa indawo ye-loop okanye ukonyusa umgama phakathi kwe-loops yokudibanisa kuya kunciphisa isiphumo. Indawo yeluphu ihlala incitshiswa iye kubuncinci kwaye umgama phakathi kokudibanisa iziporo uyandiswa. Ukukhusela ngemagnethi ngamanye amaxesha kuyadingeka, kodwa kuyabiza kwaye kuthambekele ekusileleni koomatshini, ke yiphephe.
11. Q: Kwi-Q & A yeeNjineli zesicelo, indlela yokuziphatha engeyiyo efanelekileyo yeesekethe ezihlanganisiweyo ihlala ikhankanywa. Kuya kuba lula ukusebenzisa izinto ezilula ezinje ngokuchasene. Chaza ukusondela kwezinto ezifanelekileyo.
A: Ndifuna nje ukuba isichasi sibe sisixhobo esifanelekileyo, kodwa isilinda esifutshane ekukhokeleni kwesixhathisi sisebenza ngokufana nesixhathisi esicocekileyo. Eyona nto inokuxhathisa ikwaqulathe icandelo lokumelana nengcinga-icandelo lokuphendula kwakhona. Uninzi lwabachasi banamandla amancinci amancinci (ngesiqhelo i-1 ukuya kwi-3pF) ngokuhambelana nokuxhathisa kwabo. Nangona abanye abachasayo befilimu, ukusika kwe-helical groove kwiifilimu zabo ezichasayo kuninzi okunyanzelisayo, ukuphendula kwabo ngokungahambi kakuhle ngamashumi okanye ngamakhulu e-nahen (nH). Ewe, ukumelana nenxeba ngocingo kuhlala kunganyanzelekanga kunokuba kubenamandla (ubuncinci kumaza asezantsi). Emva kwayo yonke loo nto, izixhobo zokuxhathisa ezenziwe ngocingo zenziwe ngekhoyili, ke ayisiyonto ingaqhelekanga ukuba izixhobo zokuxhathisa ngenxeba zibe neziphumo ze-microhm (μH) okanye amashumi e-microhm, okanye izinto ezibizwa ngokuba zii-“non-inductive” wire-wound resistors . Ukuze inductance eveliswe ziziqingatha ezibini zekhoyili iyarhoxa enye nenye) ikwanayo ne-1μH okanye ngaphezulu kokuchithwa okushiyekileyo. Kwixabiso eliphezulu lokuxhathisa inxeba ngocingo olungaphezulu kwe-10k ω, izixhasi ezishiyekileyo ubukhulu becala zinamandla kunokuba zibambe, kwaye amandla afikelela kwi-10pF, aphezulu kunalawo omgangatho bhanyabhanya omncinci okanye izixhathisi zokwenziwa. Oku kusabela kufuneka kuthathelwe ingqalelo ngononophelo xa kuyilwa iisekethi ezihamba rhoqo ezinee-resistors.
Q: Kodwa uninzi lweesekethe ozichazayo zisetyenziselwa imilinganiselo echanekileyo kwiDC okanye kumaza asezantsi kakhulu. I-inductors ezilahlekileyo kunye ne-capacitors ezilahlekileyo azinamsebenzi kwezi zicelo, akunjalo?
A: ewe. Ngenxa yokuba ii-transistors (zombini zinqamlezileyo kwaye zingaphakathi kwiisekethi ezihlanganisiweyo) zinobubanzi obubanzi kakhulu beebhendi, ii-oscillation ngamanye amaxesha zinokwenzeka kumakhulu okanye kumawaka amabhendi e-megahertz xa isekethe iphela ngomthwalo onokubangela. Ukususwa kunye nokulungiswa kwezenzo ezinxulumene nokushiyeka kuneziphumo ezibi kukuchaneka kwesantya esiphantsi kunye nozinzo.
Okubi nangakumbi kukuba, ii-oscillation zisenokungabonakali kwi-oscilloscope nokuba kungenxa yokuba ibhendi ye-oscilloscope iphantsi kakhulu xa kuthelekiswa nobubanzi bebhendi yesantya esisezantsi sokulinganiswa, okanye ngenxa yokuba amandla e-oscilloscope probe anele ukumisa ii-oscillations. Eyona ndlela isebenzayo kukusebenzisa ibhendi ebanzi (isantya esisezantsi ukuya kwi-15GHz apha ngasentla) i-spectrum analyzer ukujonga inkqubo ye-oscillations ye-parasitic. Olu luqwalaselo kufuneka lwenziwe xa igalelo lahluka ngokwalo lonke uluhlu olunamandla, kuba ukususwa kwe-parasitic ngamanye amaxesha kwenzeka kuluhlu olucekeceke lwebhanti yokufaka.
Umbuzo: Ngaba ikhona imibuzo malunga nokumelana nezinto?
A: Ukuxhathisa kwesixhathisi akulungisekanga, kodwa kuyahluka kubushushu. Ubushushu bokulingana (TC) buyahluka ukusuka kwi-PPM / ° C (yezigidi ngedigri yeCelsius) ukuya kumawakawaka ePPM / ° C. Ezona zixhathisi zizinzileyo zizilonda ezenziwe ngocingo okanye ezomeleleyo kwifilimu, kwaye ezona zimbi zezinto zokumelana nefilimu zekhabhoni.
Ama-coefficients amaqondo obushushu amakhulu ngamanye amaxesha anokuba luncedo (a + 3500ppm / ° C resistor can be used to compensate for kT / Q in the junction diode character equation, as ngaphambili khankanywe kwi-Q & A yeenjineli zesicelo). Kodwa ekuchaseni ngokubanzi ngamaqondo obushushu kunokuba sisiseko sempazamo kwiisekethi ezichanekileyo.
Ukuba ukuchaneka kwesekethe kuxhomekeke kumdlalo wee-resistors ezimbini ezinee-coefficients zobushushu ezahlukeneyo, ke nokuba kungangqinelana njani kakuhle kwiqondo elinye lobushushu, alizukuhambelana kwelinye. Nokuba i-coefficients yeqondo lobushushu lezinto ezimbini ezichasayo ziyangqinelana, akukho siqinisekiso sokuba ziya kuhlala kubushushu obufanayo. Ukuzifudumeza ngokwakho okuveliswa kukusetyenziswa kwamandla ngaphakathi okanye ubushushu bangaphandle obudluliselwe kumthombo wobushushu kwinkqubo kunokubangela ukungalingani kweqondo lobushushu, okukhokelela kukumelana. Nditsho nomgangatho ophezulu wocingo-inxeba okanye isinyithi-ifilimu enokumelana nayo inokuba neqondo lobushushu elingalinganiyo lamakhulu (okanye amawaka) i-PPM / ℃. Isisombululo esicacileyo kukusebenzisa izinto ezimbini zokuxhathisa ezakhelweyo ukuze zombini zisondele kwimatrix efanayo, ukuze inkqubo ichaneke kakuhle ngalo lonke ixesha. I-substrate inokuba ziziciko ze-silicon ezilinganisa iisekethe ezihlanganisiweyo ezichanekileyo, iifers zeglasi okanye iifilimu zesinyithi. Nokuba yeyiphi i-substrate, ii-resistors ezimbini ziyahambelana kakuhle ngexesha lokwenziwa, zinee-coefficients zobushushu ezihambelana kakuhle, kwaye ziphantse kubushushu obufanayo (kuba zisondele kakhulu).