Li-filter capacitor, li-inductors tsa mokhoa o tloaelehileng, le lifaha tsa makenete ke lipalo tse tloaelehileng lipotolohong tsa moralo oa EMC, hape ke lisebelisoa tse tharo tse matla ho felisa tšitiso ea motlakase.
Bakeng sa karolo ea bana ba bararo potolohong, ke lumela hore ho na le baenjiniere ba bangata ba sa utloisiseng, sengoloa se tsoang ho moralo oa tlhahlobo e qaqileng ea molao-motheo oa ho felisa tse tharo tse bohale ka ho fetisisa tsa EMC.
1.Filter capacitor
Le hoja resonance ea capacitor e sa ratehe ho tloha sebakeng sa pono ea ho hloekisa lerata le phahameng la maqhubu, resonance ea capacitor ha e kotsi kamehla.
Ha makhetlo a lerata a lokelang ho hloekisoa a behiloe, bokhoni ba capacitor bo ka fetoloa e le hore ntlha ea resonant e oele feela ka makhetlo a tšitiso.
Boenjiniere bo sebetsang, khafetsa lerata la motlakase le lokelang ho sefshoa hangata le fihla ho makholo a MHz, kapa ho feta 1GHz. Bakeng sa lerata le joalo la maqhubu a phahameng a motlakase, hoa hlokahala ho sebelisa "capacitor" ea "capacitor" ho sefa hantle.
Lebaka leo ka lona li-capacitor tse tloaelehileng li sa khoneng ho sefa lerata le phahameng haholo ke ka mabaka a mabeli:
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(2) Lebaka le leng ke hore capacitance ea parasitic pakeng tsa lithapo tse kopanyang letšoao la maqhubu a phahameng, ho fokotsa phello ea ho hloekisa.
Lebaka leo ka lona "capacitor" ea "capacitor" e ka sefang lerata le phahameng haholo ke hore "capacitor" ha e na bothata ba hore inductance ea lead e etsa hore frequency ea capacitor resonance e tlase haholo.
'Me ka-core capacitor e ka kenngoa ka ho toba holim'a phanele ea tšepe, e sebelisa tšepe ea tšepe ho bapala karolo ea ho itšehla thajana ho phahameng. Leha ho le joalo, ha u sebelisa through-core capacitor, bothata boo u lokelang ho bo ela hloko ke bothata ba ho kenya.
Bofokoli bo boholo ba "capacitor" ea "capacitor" ke tšabo ea mocheso o phahameng le tšusumetso ea mocheso, e bakang mathata a maholo ha ho tjheseletsa ka-core capacitor ho phanele ea tšepe.
Li-capacitor tse ngata li senyehile nakong ea welding. Haholo-holo ha palo e kholo ea li-core capacitor e hloka ho kenngoa phanele, hafeela ho na le tšenyo, ho thata ho e lokisa, hobane ha capacitor e senyehileng e tlosoa, e tla baka tšenyo ho li-capacitor tse ling tse haufi.
2.Common mode inductance
Kaha mathata a EMC a tobanang le ona hangata ke tšitiso ea mekhoa e tloaelehileng, li-inductors tsa mekhoa e tloaelehileng le tsona ke e 'ngoe ea likarolo tsa rona tse matla tse sebelisoang hangata.
Tloaelehileng mode inductor ke mokhoa o tloaelehileng tšitiso khatello sesebelisoa le ferrite e le konokono, e leng e na le dikhoele tse peli tsa boholo bo lekanang le palo e tšoanang ea thinya symmetrically leqeba ka e tšoanang ferrite lesale makenete konokono ho theha sesebediswa tse 'nè-terminal, eo. e na le phello e kholo ea khatello ea inductance bakeng sa lets'oao la mokhoa o tloaelehileng, le inductance e nyane ea ho lutla bakeng sa lets'oao la mokhoa oa phapang.
Molao-motheo ke hore ha mokhoa o tloaelehileng oa hona joale o phalla, matla a khoheli ka har'a selikalikoe a khoheli a phahame, kahoo a na le inductance e kholo, e thibelang mokhoa o tloaelehileng oa hona joale, 'me ha li-coil tse peli li phalla ka mokhoa o fapaneng oa hona joale, matla a khoheli. ka selikalikoe sa makenete e hlakola e mong le e mong, 'me ho na le hoo e ka bang ha ho na inductance, kahoo mokhoa oa ho khetholla hona joale o ka feta ntle le ho fokotseha.
Ka hona, mokhoa o tloaelehileng oa inductor o ka thibela ka katleho pontšo e tloaelehileng ea ho kena-kenana le mokhoa o tloaelehileng, empa ha o na phello ho phetiso e tloaelehileng ea pontšo ea mokhoa oa ho khetholla.
Li-inductors tsa mokhoa o tloaelehileng li lokela ho fihlela litlhoko tse latelang ha li etsoa:
(1) The lithapo leqeba holim'a coil mantlha lokela ho insulated ho etsa bonnete ba hore ha ho na ho senyeha ha potoloho e khutšoanyane pakeng tsa thinya ea khoele tlas'a ketso ea overvoltage hang-hang;
(2) Ha khoele e phalla ka har'a motlakase o moholo oa hang-hang, motsoako oa makenete ha oa lokela ho tlala;
(3) The makenete konokono ka khoele e lokela ho insulated ho tloha khoele ho thibela ho robeha pakeng tsa tse peli tlas'a ketso ea overvoltage hang-hang;
(4) Khoeli e lokela ho etsoa ka lera le le leng ka hohle kamoo ho ka khonehang, e le ho fokotsa bokhoni ba parasitic ea coil le ho ntlafatsa bokhoni ba khoele ho fetisetsa ho overvoltage ea nakoana.
Tlas'a maemo a tloaelehileng, ha re ntse re ela hloko khetho ea sehlopha sa maqhubu a hlokahalang ho sefa, ho ba le tšusumetso e kholo ea mokhoa o tloaelehileng, ho molemo, kahoo re hloka ho sheba lintlha tsa lisebelisoa ha re khetha inductor ea mekhoa e tloaelehileng, haholo-holo ho latela impedance frequency curve.
Ho phaella moo, ha u khetha, ela hloko phello ea mekhoa e fapaneng ea ho thibela pontšo ka pontšo, haholo-holo e lebisang tlhokomelo ho mekhoa e fapaneng ea impedance, haholo-holo ho ela hloko likou tse lebelo le phahameng.
3.Sefaha sa Magnetic
Ts'ebetsong ea moralo oa lihlahisoa tsa dijithale tsa EMC, hangata re sebelisa lifaha tsa makenete, thepa ea ferrite ke tšepe-magnesium alloy kapa tšepe-nickel alloy, thepa ena e na le matla a phahameng a matla a khoheli, e ka ba mohlohlelletsi lipakeng tsa maqhubu a coil maemong a phahameng. maqhubu le ho hanyetsa phahameng generated capacitance bonyane.
Lisebelisoa tsa Ferrite hangata li sebelisoa ka maqhubu a phahameng, hobane maemong a tlase litšoaneleho tsa bona tsa mantlha tsa inductance li etsa hore tahlehelo moleng e be nyane haholo. Li-frequencies tse phahameng, haholo-holo ke li-reactance character ratios le phetoho ka makhetlo. Lits'ebetsong tse sebetsang, lisebelisoa tsa ferrite li sebelisoa e le li-attenuators tse phahameng tsa maqhubu a seea-le-moea.
Ha e le hantle, ferrite e lekana hantle le ho lumellana le ho hanyetsa le ho kenya letsoho, ho hanyetsa ho khutsufatsoa ke inductor ka maqhubu a tlaase, 'me impedance ea inductor e fetoha e phahameng haholo ka makhetlo a mangata, e le hore hona joale bohle ba fete ka ho hanyetsa.
Ferrite ke sesebelisoa se jang seo matla a phahameng-frequency a fetoloang ho matla a mocheso, a khethiloeng ke litšobotsi tsa oona tsa ho hanyetsa motlakase. Lifaha tsa makenete tsa Ferrite li na le litšobotsi tse betere tsa ho sefa khafetsa ho feta li-inductors tse tloaelehileng.
Ferrite e hanyetsana le maqhubu a phahameng, e lekanang le inductor e nang le boleng bo tlaase haholo, kahoo e ka boloka ho thibela ho phahama ho feta mefuta e mengata ea maqhubu, kahoo e ntlafatsa bokhoni ba ho sefa maqhubu a phahameng.
Ka sehlopha sa maqhubu a tlaase, impedance e entsoe ka inductance. Ka maqhubu a tlase, R e nyane haholo, 'me matla a khoheli a mantlha a phahame, kahoo inductance e kholo. L e bapala karolo e kholo, 'me tšitiso ea motlakase e hatelloa ke ho thuisa. 'Me ka nako ena, tahlehelo ea matla a khoheli e nyane, sesebelisoa sohle ke tahlehelo e tlase, litšoaneleho tse phahameng tsa Q tsa inductor, inductor ena e bonolo ho baka resonance, kahoo sehlopheng se tlase sa maqhubu, ka linako tse ling ho ka ba le tšitiso e ntlafalitsoeng. ka mor'a ho sebelisa lifaha tsa makenete tsa ferrite.
Ka sehlopha se phahameng sa maqhubu, impedance e entsoe ka likarolo tsa ho hanyetsa. Ha maqhubu a ntse a eketseha, ho kenella ha motsoako oa magnetic ho fokotseha, ho fella ka ho fokotseha ha inductance ea inductor le ho fokotseha ha karolo ea inductive reactance.
Leha ho le joalo, ka nako ena, tahlehelo ea matla a khoheli e eketseha, karolo ea ho hanyetsa ea eketseha, e leng se bakang keketseho ea ho thibela ho feletseng, 'me ha lets'oao la maqhubu a phahameng le feta ferrite, ho kena-kenana le motlakase ho kenngoa le ho fetoloa sebopeho. ya ho qhala mocheso.
Likarolo tsa khatello ea Ferrite li sebelisoa haholo libotong tsa potoloho tse hatisitsoeng, likhoele tsa matla le mehala ea data. Mohlala, ntho ea khatello ea ferrite e eketsoa pheletsong ea thapo ea matla ea boto e hatisitsoeng ho sefa tšitiso ea maqhubu a phahameng.
Sefaha sa makenete sa Ferrite kapa sefaha sa makenete se sebelisoa ka ho khetheha ho hatella tšitiso ea maqhubu a phahameng le tšitiso ea tlhoro mehalang ea mats'oao le lithapo tsa motlakase, 'me e boetse e na le bokhoni ba ho monya tšitiso ea methapo ea methapo ea motlakase. Tšebeliso ea lifaha tsa chip magnetic kapa chip inductors haholo-holo e ipapisitse le ts'ebeliso e sebetsang.
Li-inductors tsa chip li sebelisoa lipotolohong tse resonant. Ha lerata le sa hlokahaleng la EMI le hloka ho felisoa, tšebeliso ea lifaha tsa chip magnetic ke khetho e ntle ka ho fetisisa.
Tšebeliso ea lifaha tsa chip magnetic le chip inductors
Li-inductors tsa chip:Maqhubu a seea-le-moea (RF) le likhokahano tse se nang mohala, lisebelisoa tsa theknoloji ea tlhahisoleseling, lisebelisoa tsa radar, lisebelisoa tsa elektronike tsa likoloi, lithelefono tsa cellular, li-pager, lisebelisoa tsa molumo, lisebelisoa tsa botho tsa digital (PDAs), lisebelisoa tsa ho laola hole le mohala, le li-module tsa motlakase tse tlaase.
Chip magnetic beads:Li-circuits tse hlahisang oache, ho sefa lipakeng tsa li-circuits tsa analog le tsa dijithale, lihokelo tsa I/O tsa ho kenya/ho ntša (joalo ka likou tsa serial, likou tse tšoanang, likonopo, litoeba, likhokahano tsa mehala e telele, marang-rang a sebaka sa heno), li-circuits tsa RF le lisebelisoa tsa kelello tse hlaselehang habonolo. tšitiso, ho sefa ha tšitiso e phahameng-frequency e etsoang lipotolohong tsa phepelo ea motlakase, likhomphutha, bahatisi, lirekoto tsa video (VCRS), khatello ea lerata ea EMI lits'ebetsong tsa thelevishene le mehala ea cellular.
Yuniti ea sefaha sa makenete ke li-ohms, hobane yuniti ea sefaha sa makenete ke lebitso ho latela ts'ireletso eo e e hlahisang ka makhetlo a itseng, 'me unit of impedance le eona ke ohms.
The magnetic bead DATASHEET e tla fana ka kakaretso ea makhetlo a mangata le litšobotsi tse sitisang mothinya, hangata 100MHz joalo ka tloaelo, mohlala, ha maqhubu a 100MHz ha sefaha sa makenete se lekana le 1000 ohms.
Bakeng sa frequency band eo re batlang ho e sefa, re hloka ho khetha sets'oants'o se seholo sa sefaha sa makenete, se betere, hangata re khetha 600 ohm impedance kapa ho feta.
Ntle le moo, ha u khetha lifaha tsa makenete, hoa hlokahala ho ela hloko phallo ea lifaha tsa makenete, tseo ka kakaretso li hlokang ho fokotsoa ke 80%, mme tšusumetso ea DC impedance ho theoha ha motlakase e lokela ho nahanoa ha e sebelisoa lipotolohong tsa motlakase.
Nako ea poso: Jul-24-2023
