nkhani

Ngakhale kutsokomola wamba kumakhala kotchuka, kuthekera kwina ndi fyuluta ya monolithic EMI. Ngati masanjidwewo ndi omveka, zigawo za ceramic za multilayer zitha kupereka njira yabwino kwambiri yochepetsera phokoso.
Zinthu zambiri zimachulukitsa kuchuluka kwa kusokoneza kwa "phokoso" komwe kungawononge kapena kusokoneza magwiridwe antchito a zida zamagetsi. Masiku ano galimoto ndi chitsanzo. M'galimoto, mutha kupeza Wi-Fi, Bluetooth, wailesi ya satellite, machitidwe a GPS, ndipo ichi ndi chiyambi chabe. Pofuna kuthana ndi kusokoneza kwamtunduwu, makampani nthawi zambiri amagwiritsa ntchito zotchinga ndi EMI zosefera kuti athetse phokoso losafunikira. Koma tsopano njira zina zachikhalidwe zochotsera EMI/RFI sizikugwiranso ntchito.
Vutoli lapangitsa ma OEM ambiri kupewa zisankho monga 2-capacitor differential, 3-capacitor (imodzi X capacitor ndi ma Y capacitors awiri), zosefera feedthrough, kutsamwitsidwa wamba, kapena kuphatikiza kwa izi kuti mupeze mayankho oyenera. Mwachitsanzo, mu fyuluta ya Monolithic EMI yokhala ndi phokoso labwinoko pamaphukusi ang'onoang'ono.
Zida zamagetsi zikalandira mafunde amphamvu a electromagnetic, mafunde osafunikira amatha kupangitsidwa kuzungulira ndikuyambitsa ntchito mosayembekezereka-kapena kusokoneza ntchito yomwe akufuna.
EMI/RFI ikhoza kukhala mu mawonekedwe a mpweya wochitidwa kapena woyaka. EMI ikachitidwa, zikutanthauza kuti phokoso limafalikira pamagetsi amagetsi. Phokoso likamafalitsidwa mumlengalenga ngati maginito kapena mafunde a wailesi, EMI yotulutsa imachitika.
Ngakhale mphamvu yogwiritsidwa ntchito kuchokera kunja ndi yaying'ono, ngati itasakanizidwa ndi mafunde a wailesi omwe amagwiritsidwa ntchito poulutsa ndi kulankhulana, izi zingayambitse kulephera kulandira, phokoso lachilendo, kapena kusokoneza mavidiyo. Ngati mphamvuyo ndi yamphamvu kwambiri, zida zamagetsi zimatha kuwonongeka.
Kochokera kumaphatikizapo phokoso lachilengedwe (monga kutulutsa ma electrostatic, kuyatsa, ndi zina) ndi phokoso lopanga (monga phokoso lolumikizana, kugwiritsa ntchito zida zotayikira pafupipafupi, ma radiation oyipa, ndi zina zotero). Nthawi zambiri, phokoso la EMI / RFI ndilo phokoso lamtundu wamba, kotero yankho ndilo kugwiritsa ntchito zosefera za EMI kuchotsa ma frequency osafunika ngati chipangizo chosiyana kapena chophatikizidwa mu bolodi ladera.
EMI fyuluta EMI fyuluta nthawi zambiri amapangidwa ndi zinthu zopanda pake, monga ma capacitors ndi inductors, omwe amalumikizidwa kuti apange dera.
"Ma inductors amalola DC kapena ma frequency otsika kuti adutse, ndikutsekereza mafunde owopsa osafunikira. Ma capacitors amapereka njira yochepetsera kusuntha phokoso lapamwamba kwambiri kuchokera pa kulowetsa kwa fyuluta kubwerera ku mphamvu kapena kugwirizanitsa pansi, "anatero Johanson Dielectrics Christophe Cambrelin adati kampaniyo imapanga multilayer ceramic capacitors ndi EMI zosefera.
Njira zosefera zachizoloŵezi zodziwika bwino zimaphatikizapo zosefera zotsika pang'ono pogwiritsa ntchito ma capacitor omwe amadutsa ma siginecha okhala ndi ma frequency otsika kuposa ma frequency osankhidwa ndikuchepetsa ma siginecha okhala ndi ma frequency apamwamba kuposa ma frequency odulira.
Choyambira chodziwika bwino ndikuyika ma capacitor pamasinthidwe osiyanitsira, pogwiritsa ntchito capacitor pakati pa mzere uliwonse ndi pansi pazolowera zosiyanitsira. Fyuluta ya capacitor munthambi iliyonse imasamutsa EMI/RFI pansi pamwamba pa mafupipafupi odulidwa. Popeza kusinthaku kumaphatikizapo kutumiza zizindikiro za gawo losiyana kupyolera mu mawaya awiri, kumapangitsa kuti phokoso likhale lopanda phokoso pamene likutumiza phokoso losafunikira pansi.
"Mwatsoka, mtengo wa capacitance wa MLCCs ndi X7R dielectrics (omwe amagwiritsidwa ntchito pa ntchitoyi) amasiyana kwambiri ndi nthawi, kutentha kwapadera, ndi kutentha," adatero Cambrelin.
"Choncho ngakhale ma capacitor awiriwa atakhala ofanana kwambiri kutentha kwa chipinda ndi magetsi otsika, panthawi inayake, nthawi, magetsi, kapena kutentha kwasintha, amatha kukhala ndi makhalidwe osiyana kwambiri. Mtundu woterewu wapakati pa mizere iwiri Kusagwirizana kungayambitse mayankho osafanana pafupi ndi kudulidwa kwa fyuluta. Chifukwa chake, amasintha phokoso lamtundu wina kukhala phokoso losiyana. ”
Njira ina ndiyo kulumikiza capacitor yamtengo wapatali "X" pakati pa ma capacitor awiri a "Y". "X" capacitor shunt imatha kupereka njira yofananira yofananira, koma idzatulutsa zosefera zosiyanitsa zosafunikira. Mwina njira yodziwika bwino komanso njira yosinthira zosefera zotsika ndizomwe zimatsamwitsa.
Mtundu wamba wotsamwitsa ndi 1: 1 thiransifoma momwe ma windings onse amakhala ngati pulayimale ndi sekondale. Mwanjira imeneyi, mafunde omwe amadutsa panjira imodzi imapangitsa kuti mafunde ena azitha kulowera kwina. Tsoka ilo, kutsokomola wamba kumakhalanso kolemetsa, kokwera mtengo, komanso kumakonda kulephera chifukwa cha kugwedezeka.
Komabe, njira yabwino wamba kutsamwitsidwa ndi kufananiza koyenera ndi kulumikizana pakati pa ma windings amawonekera ku ma siginecha osiyanitsira ndipo imakhala yolepheretsa kwambiri phokoso wamba. Choyipa chimodzi cha kutsamwitsa wamba ndikuchepa kwafupipafupi komwe kumachitika chifukwa cha mphamvu ya parasitic. Pazinthu zapakatikati, kukweza kwa inductance yomwe imagwiritsidwa ntchito kupeza kusefa kwafupipafupi, kuchuluka kwa makhoti ofunikira ndi mphamvu ya parasitic yomwe imabwera nayo, zomwe zimapangitsa kusefa kwafupipafupi kusagwira ntchito.
Kusagwirizana pakulolerana kwamakina pakati pa ma windings kungayambitse kutembenuka kwa ma mode, momwe gawo la mphamvu ya chizindikiro limasandulika kukhala phokoso wamba, ndi mosemphanitsa. Izi zipangitsa kuti ma electromagnetic agwirizane komanso chitetezo chokwanira. Kusagwirizana kumachepetsanso inductance yogwira mtima ya mwendo uliwonse.
Mulimonsemo, pamene chizindikiro chosiyanitsa (chiphaso) chimagwira ntchito mofanana ndi phokoso lamtundu wamba lomwe liyenera kuponderezedwa, njira yodziwika bwino imakhala ndi mwayi waukulu kuposa zina. Pogwiritsa ntchito kutsamwitsa wamba, chizindikiro cholowera chimatha kukulitsidwa mpaka pamtundu wamba woyimitsa.
Zosefera za Monolithic EMI Ngakhale zosefera zamtundu wamba ndizodziwika, kuthekera kwina ndi zosefera za monolithic EMI. Ngati masanjidwewo ndi omveka, zigawo za ceramic za multilayer zitha kupereka njira yabwino kwambiri yochepetsera phokoso. Amaphatikiza ma capacitor awiri ofananira mu phukusi limodzi, lomwe lili ndi kuletsa kwapawiri komanso zoteteza. Zoseferazi zimagwiritsa ntchito njira ziwiri zamagetsi zodziyimira pawokha pachipangizo chimodzi cholumikizidwa ndi kulumikizana kwakunja zinayi.
Pofuna kupewa chisokonezo, ziyenera kudziwidwa kuti fyuluta ya monolithic EMI si chikhalidwe cha feedthrough capacitor. Ngakhale amawoneka ofanana (phukusi lofanana ndi maonekedwe), mapangidwe awo ndi osiyana kwambiri, ndipo njira zawo zolumikizira ndizosiyana. Monga zosefera zina za EMI, fyuluta ya monolithic EMI imachepetsa mphamvu zonse pamwamba pa mafupipafupi odulidwa, ndikusankha mphamvu yofunikira kuti idutse, ndikusamutsa phokoso losafunikira ku "nthaka".
Komabe, chinsinsi chake ndi inductance yotsika kwambiri komanso yofananira ndi impedance. Pazosefera za monolithic EMI, cholumikiziracho chimalumikizidwa mkati ndi ma elekitirodi wamba (zotchingira) mu chipangizocho, ndipo bolodi imasiyanitsidwa ndi ma elekitirodi. Pankhani ya magetsi osasunthika, ma node atatu amagetsi amapangidwa ndi magawo awiri a capacitive, omwe amagawana ma elekitirodi wamba, maelekitirodi onse owerengera amakhala mu thupi limodzi la ceramic.
Kuchulukana pakati pa magawo awiri a capacitor kumatanthauzanso kuti zotsatira za piezoelectric ndizofanana ndi zosiyana, kulepheretsana. Ubale umenewu umakhudzanso kusintha kwa kutentha ndi magetsi, kotero kuti zigawo za mizere iwiriyi zimakhala ndi digiri yofanana ya ukalamba. Ngati zosefera za monolithic EMI zili ndi vuto, sizingagwiritsidwe ntchito ngati phokoso lamtundu wamba ndilofanana pafupipafupi ndi chizindikiro chosiyana. "Pamenepa, kutsamwitsa wamba ndi njira yabwinoko," adatero Cambrelin.
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