Kusanthula ndi Kuchepetsa Phokoso la Magetsi mu High-Frequency PCB Design process

Mu PCB yapamwamba kwambiris, phokoso lamagetsi limawonekera ngati njira yosokoneza. Nkhaniyi ikuwunikira mwatsatanetsatane mawonekedwe ndi magwero a phokoso lamagetsi pama PCB othamanga kwambiri, ndipo imapereka mayankho othandiza komanso ogwira mtima potengera ntchito zamainjiniya.

A.Kusanthula Phokoso la Magetsi

Phokoso lamagetsi limatanthawuza phokoso lomwe limapangidwa kapena kusokonezedwa ndi magetsi omwewo. Kusokoneza uku kumawonekera m'mbali zotsatirazi:

1. Phokoso lofalitsidwa chifukwa chachibadwa impedancewa magetsi. M'mabwalo othamanga kwambiri, phokoso lamagetsi limakhudza kwambiri ma frequency apamwamba. Choncho, chofunika choyamba ndi phokoso lochepamagetsi. Zofunikanso chimodzimodzi ndi nthaka yoyera komanso magetsi.

Muzochitika zabwino, magetsi angakhalewopanda impedance, zomwe zimapangitsa kuti pasakhale phokoso. Komabe, pochita, magetsi amakhala ndi vuto linalake, lomwe limagawidwa pamagetsi onse, zomwe zimapangitsa kuti phokoso likhale lokwera kwambiri. Chifukwa chake, kuyesayesa kuyenera kuchitidwa kuti muchepetse kutsekeka kwa magetsi. Ndikwabwino kukhala odzipereka ndege yamagetsindindege yapansi. Pamapangidwe amagetsi othamanga kwambiri, nthawi zambiri imakhala yothandiza kwambiri kupanga magetsi m'magawo m'malo mokhala ngati mabasi, kuwonetsetsa kuti lupuyo imatsata njira mosavutikira. Kuphatikiza apo, gulu lamagetsi limapereka achizindikiro champhamvupazizindikiro zonse zopangidwa ndi kulandiridwa pa PCB, potero kuchepetsa kuzungulira kwa siginecha ndikuchepetsa phokoso.

2. Kusokoneza kwa Common Mode Field: Kusokoneza kwamtunduwu kumakhudzana ndi phokoso lapakati pa magetsi ndi pansi. Zimachokera ku kusokoneza komwe kumachitika chifukwa cha lupu lopangidwa ndi dera losokonekera komanso ma voliyumu wamba omwe amabwera chifukwa cha malo omwe amapezeka. Kukula kumadalira mphamvu zamagetsi ndi maginito, ndipo mphamvu yake ndi yochepa.

Muzochitika izi, kuchepa kwaposachedwa (Ic) kumabweretsa mphamvu yamagetsi wamba pamndandandaloop panopa, kukhudza gawo lolandira. Ngati ndimaginitoimatsogolera, ma voliyumu wamba omwe amapangidwa mumndandanda wamtundu wapansi amaperekedwa ndi formula:

ΔB mu fomula (1) imayimira kusintha kwamphamvu ya maginito, yoyesedwa mu Wb/m²; S amatanthauza chigawo cha m².

Za aelectromagnetic field, pamene malo amagetsi mtengo umadziwika, mphamvu yamagetsi yoyendetsedwa imaperekedwa ndi Equation (2), yomwe nthawi zambiri imagwira ntchito L=150/F kapena kuchepera, ndipo F ikuyimiraelectromagnetic wave frequencymu MHz. Ngati malirewa apyola, kuwerengera kwa voteji yowonjezereka kumatha kusinthidwa motere:

3. Differential Mode Field Interference: Izi zikutanthauza kusokoneza pakati pa magetsi ndi magetsikulowetsa ndi kutulutsa mphamvus. M'mapangidwe enieni a PCB, wolemba adawona kuti kuthandizira kwake paphokoso lamagetsi ndikocheperako, motero kuyenera kusiyidwa pano.
4. Kusokoneza kwa Interline: Kusokoneza kwamtunduwu kumakhudzana ndi kusokoneza pakati pa zingwe zamagetsi. Pakakhala mphamvu yolumikizana (C) ndi kutsatana (M1-2) pakati pa mabwalo awiri ofananira, kusokonezako kumawonekera pagawo losokonezedwa ngati pali voteji (VC) ndi yapano (IC) pagawo losokoneza:
   1. Mpweya wophatikizidwa ndi capacitive impedance umaperekedwa ndi Equation (4), pamene RV imayimira mtengo wofanana wakukana kwapafupindikukana kutalichadera losokoneza.
   2. Kukaniza kwa Series kudzera pakuphatikizana kochititsa chidwi: Ngati pali phokoso lodziwika bwino pamagwero osokoneza, kusokoneza kwa interline nthawi zambiri kumawoneka munjira zofananira komanso zosiyana.
5. Kulumikizana kwa Power Line: Chodabwitsa ichi chimachitika pamene chingwe chamagetsi chimatumiza zosokoneza pazida zina pambuyo poyesedwaelectromagnetic kusokonezakuchokera ku AC kapena DC gwero lamphamvuIzi zikuyimira njira yosalunjika ya kusokoneza kwa phokoso lamagetsi maulendo apamwamba kwambiris. Ndikofunika kuzindikira kuti phokoso lamagetsi silingakhale lodzipangira lokha, koma likhozanso chifukwa cha kusokoneza kwakunja, zomwe zimapangitsa kuti phokoso likhale lopangidwa ndi lokha (lotenthedwa kapena lopangidwa) lokha, potero limasokoneza mabwalo ena kapena zipangizo zina.

• Njira Zothetsera Kusokoneza Phokoso la Magetsi

Poganizira mawonetseredwe osiyanasiyana ndi zomwe zimayambitsa kusokoneza kwa phokoso lamagetsi zomwe zafufuzidwa pamwambapa, zomwe zimatsogolera ku phokoso lamagetsi zimatha kusokonezedwa makamaka, kupondereza kusokoneza. Njira zotsatirazi ndizovomerezeka:

• KusamaliraBoard Kupyolera mu Holes: Kudzera mabowo zofunikaetching kutsegulas pagawo lamagetsikuti alandire ndime yawo. Ngati kutseguka kwa gawo la mphamvu kuli kwakukulu kwambiri, kumatha kukhudza kuzungulira kwa siginecha, kukakamiza chizindikiro kuti chidutse ndikuwonjezera malo ozungulira ndi phokoso. Ngati mizere ina yazizindikiro yakhazikika pafupi ndi potsegulira ndikugawana loop, kusokoneza wamba kumatha kuyambitsa kuphatikizika.
• Waya Wokwanira Pansi pa Ma Cable: Chizindikiro chilichonse chimafunikira chizindikiro chake chodzipatulira, ndi chizindikiro ndi malo ozungulira amasungidwa ang'onoang'ono momwe angathere, kuwonetsetsa kulumikizana kofanana.
• Kuyika kwa Zosefera Phokoso Lamphamvu: Fyulutayi imatsitsa bwino phokoso lamkati lamagetsi, makina owonjezera.odana ndi kusokonezandi chitetezo. Zimagwira ntchito ngati njira ziwiriRF fyuluta, kusefa zosokoneza zaphokoso zomwe zimayambitsidwa kuchokera ku chingwe chamagetsi (kuteteza kusokoneza kwa zipangizo zina) ndi phokoso lopangidwa palokha (kupewa kusokoneza zipangizo zina), komanso kusokoneza wamba wamba.
• Kudzipatula kwa MphamvuTransformer: Izi zimalekanitsa wamba-mode ground loop yamagetsi loopo signal cable, kulekanitsa bwino ma wamba-mode loop current opangidwa pa ma frequency apamwamba.
• Kuwongolera Mphamvu: Kubwezeretsanso magetsi oyeretsa kumatha kuchepetsa kwambiri phokoso lamagetsi.
• Wiring: Mizere yolowera ndi yotulutsa mphamvu yamagetsi iyenera kusungidwa kutali ndi m'mphepete mwa bolodi la dielectric kuti zisapangitse ma radiation ndikusokoneza mabwalo kapena zida zina.
• Zida Zamagetsi Zosiyana za Analogi ndi Digital: Zipangizo zama frequency apamwamba nthawi zambiri zimakhala zovuta kwambiri kuphokoso la digito, kotero ziwirizi ziyenera kukhala zodzipatula ndikulumikizidwa palimodzi polowera magetsi. Ngati siginecha ikufunika kuwoloka madera onse a analogi ndi digito, lupu imatha kuyikidwa pazizindikiro kuti muchepetse malo ozungulira.
• Pewani Kuphatikizika Kwa Magetsi Osiyana Pakati pa Magawo Osiyanasiyana: Yesani kuwagwedeza kuti muteteze phokoso lamagetsi kuti lisaphatikizidwe mosavuta ndi mphamvu ya parasitic.
• Isolate Sensitive Components: Zigawo monga zokhoma magawo (PLLs) zimakhudzidwa kwambiri ndi phokoso lamagetsi ndipo ziyenera kusungidwa kutali momwe zingathere ndi magetsi.
• Kuyika kwa Chingwe Champhamvu: Kuyika chingwe chamagetsi pambali pa mzere wa siginecha, kumatha kuchepetsa kuzungulira kwa siginecha ndikukwaniritsa kuchepetsa phokoso.
• Bypass Path Grounding: Kuti mupewe phokoso lomwe lasokonekera chifukwa cha kusokoneza kwamagetsi pama board ozungulira komanso kusokoneza magetsi akunja, njira yodutsa imatha kukhazikika panjira yosokoneza (kupatula ma radiation), kulola kuti phokoso lidulidwe pansi ndikupewa kusokoneza. zida ndi zida zina.

Pomaliza:Phokoso lamagetsi, kaya lapangidwa mwachindunji kapena mosalunjika kuchokera kumagetsi, limasokoneza dera. Popondereza chikoka chake pa dera, mfundo yaikulu iyenera kutsatiridwa: kuchepetsa mphamvu ya phokoso lamagetsi pa dera komanso kuchepetsa mphamvu ya zinthu zakunja kapena dera lamagetsi kuti muteteze kuwonongeka kwa phokoso lamagetsi.