In high-frequency PCB bolodi, mtundu wofunikira kwambiri wosokoneza ndi phokoso lamagetsi. Mwa kusanthula mwadongosolo mawonekedwe ndi zomwe zimayambitsa phokoso lamphamvu pama board a PCB othamanga kwambiri, wolemba amapereka mayankho ogwira mtima komanso osavuta kuphatikiza ndi ntchito zamainjiniya.

Kusanthula kwa phokoso lamagetsi

Phokoso lamagetsi limatanthawuza phokoso lopangidwa ndi mphamvu yokhayokha kapena yoyambitsidwa ndi chisokonezo. Kusokoneza kumawonekera m’mbali zotsatirazi:

1) Phokoso lofalitsidwa chifukwa cha kulephera kwamagetsi komweko. M’mabwalo othamanga kwambiri, phokoso lamagetsi limakhudza kwambiri ma siginecha apamwamba kwambiri. Choncho, mphamvu yamagetsi yochepa imafunika poyamba. Malo oyera ndi ofunikira ngati gwero lamphamvu lamagetsi. Makhalidwe amphamvu akuwonetsedwa monga mkuyu 1.

Mphamvu waveform

Monga tikuonera pa Chithunzi 1, magetsi pansi pamikhalidwe yabwino alibe cholepheretsa, kotero palibe phokoso. Komabe, magetsi enieniwo ali ndi vuto linalake, ndipo cholepheretsacho chimagawidwa pamagetsi onse, choncho, phokoso lidzakweranso pamagetsi. Choncho, kusokoneza mphamvu kwa magetsi kuyenera kuchepetsedwa momwe mungathere, ndipo ndi bwino kukhala ndi mphamvu yodzipatulira ndi nthaka. M’mapangidwe amagetsi apamwamba kwambiri, nthawi zambiri ndi bwino kupanga magetsi ngati mawonekedwe osanjikiza kusiyana ndi mawonekedwe a basi, kotero kuti loop ikhoza kutsata njirayo ndi njira yochepetsera pang’ono. Kuphatikiza apo, bolodi lamagetsi liyeneranso kupereka cholumikizira chazizindikiro pazizindikiro zonse zopangidwa ndi kulandila pa PCB, kotero kuti kuzungulira kwazizindikiro kutha kuchepetsedwa, potero kuchepetsa phokoso.

2) Common mode kusokoneza kumunda. Amatanthauza phokoso pakati pa magetsi ndi pansi. Ndiko kusokoneza komwe kumachitika chifukwa cha voteji wamba chifukwa cha lupu lopangidwa ndi chigawo chosokonezedwa komanso malo odziwika wamba amagetsi ena. Mtengo wake umadalira gawo lamagetsi lachibale ndi maginito. Mphamvu zimadalira mphamvu. Monga momwe chithunzi 2 chikusonyezera.

Kusokoneza wamba

Panjira iyi, kutsika kwa Ic kudzayambitsa voteji wamba pamndandanda wapano, zomwe zidzakhudza gawo lomwe likulandira. Ngati mphamvu ya maginito ili yaikulu, mtengo wamagetsi wamba wopangidwa mumndandanda wapansi ndi:

Common mode voltage

Muchilinganizo (1), ΔB ndi kusintha kwa mphamvu ya maginito, Wb/m2; S ndi dera, m2.

Ngati ndi gawo lamagetsi amagetsi, pomwe mtengo wake wamagetsi umadziwika, mphamvu yake yopangidwira imakhala

Mphamvu ya inductive

Equation (2) nthawi zambiri imagwira ntchito ku L=150/F kapena kuchepera, pomwe F ndiye mafunde amagetsi amagetsi mu MHz.

Zomwe wolembayo adakumana nazo ndi izi: Ngati malirewo apyola, kuwerengera kwa voliyumu yayikulu kwambiri kumatha kusinthidwa kukhala:

Maximum induced voltage

3) Kusokonezeka kwa gawo losiyanasiyana. Imatanthawuza kusokoneza pakati pa magetsi ndi mizere yolowera ndi kutulutsa mphamvu. Mu mapangidwe enieni a PCB, wolembayo adapeza kuti gawo lake mu phokoso lamagetsi ndilochepa kwambiri, kotero sikoyenera kukambirana pano.

4) Kusokoneza pakati pa mzere. Amatanthauza kusokoneza pakati pa zingwe zamagetsi. Pakakhala mwayi wogwirizana C ndi kuyanjana kwapakati M1-2 pakati pa mabwalo awiri osiyana ofanana, ngati pali voteji VC ndi IC yamakono mu dera losokoneza, dera losokoneza lidzawoneka:

A. Mpweya wophatikizidwa ndi capacitive impedance ndi

Voltage yophatikizidwa ndi capacitive impedance

Muchilinganizo (4), RV ndi mtengo wofananira wa kukana kwapafupi-kumapeto ndi kukana kwakutali kwa dera losokonezedwa.

B. Series kukana kudzera lumikiza inductive

Series kukana kudzera inductive coupling

Ngati pali phokoso lamtundu wamba pamagwero osokoneza, kusokoneza kwa mzere ndi mzere nthawi zambiri kumatenga mawonekedwe wamba komanso kusiyanitsa.

5) Kulumikizana kwa mzere wamagetsi. Zimatanthawuza chodabwitsa kuti chingwe chamagetsi cha AC kapena DC chikalumikizidwa ndi kusokonezedwa ndi ma elekitiroma, chingwe chamagetsi chimatumiza kusokoneza kwa zida zina. Uku ndiko kusokoneza kosalunjika kwa phokoso lamagetsi kudera lapamwamba kwambiri. Tiyenera kuzindikira kuti phokoso lamagetsi silimapangidwa palokha, komanso likhoza kukhala phokoso lomwe limayambitsidwa ndi kusokoneza kwakunja, ndiyeno kukweza phokosoli ndi phokoso lopangidwa mwalokha (radiation kapena conduction) kuti asokoneze maulendo ena. kapena zipangizo.

Njira zothana ndi vuto loletsa kusokoneza kwa phokoso lamagetsi

Powona mawonetseredwe osiyanasiyana ndi zomwe zimayambitsa kusokoneza kwa phokoso lamagetsi zomwe zafufuzidwa pamwambapa, momwe zimakhalira zimatha kuwonongedwa m’njira yolunjika, ndipo kusokoneza kwa phokoso lamagetsi kumatha kuponderezedwa bwino. Mayankho ake ndi awa: 1) Samalani pobowola pa bolodi. Bowolo limafuna potsegula pagawo la mphamvu kuti likhazikike kuti lisiye danga kuti bowo lidutse. Ngati kutsegulidwa kwa gawo la mphamvu kuli kwakukulu kwambiri, mosakayikira kudzakhudza chizindikiro cha chizindikiro, chizindikiro chidzakakamizika kudutsa, malo ozungulira adzawonjezeka, ndipo phokoso lidzawonjezeka. Nthawi yomweyo, ngati mizere ina yazizindikiro ikhazikika pafupi ndi potsegulira ndikugawana loop, kulepheretsa wamba kumayambitsa crosstalk. Onani Chithunzi 3.

Lambalala njira wamba yozungulira ma sigino

2) Mawaya okwanira pansi amafunikira mawaya olumikizira. Chizindikiro chilichonse chiyenera kukhala ndi chizindikiro chake chodzipatulira, ndipo malo ozungulira chizindikiro ndi loop ndi ochepa momwe angathere, ndiye kuti, chizindikiro ndi kuzungulira ziyenera kufanana.

3) Ikani fyuluta ya phokoso lamagetsi. Ikhoza kupondereza phokoso mkati mwa magetsi ndikuwongolera zotsutsana ndi kusokoneza ndi chitetezo cha dongosolo. Ndipo ndi njira ziwiri zosefera ma radio frequency, zomwe sizingangosefa kusokoneza kwa phokoso komwe kumayambitsidwa ndi chingwe chamagetsi (kuteteza kusokoneza kwa zida zina), komanso kusefa phokoso lopangidwa palokha (kupewa kusokoneza zida zina. ), ndikusokoneza ma serial mode wamba. Zonsezi zimakhala ndi zotsatira zolepheretsa.

4) Mphamvu kudzipatula thiransifoma. Kulekanitsa lupu lamagetsi kapena njira wamba yolumikizira chingwe cha siginecha, imatha kusiyanitsa njira wamba yomwe imapangidwa pafupipafupi.

5) Wowongolera magetsi. Kubwezeretsanso magetsi oyeretsa kumatha kuchepetsa kwambiri phokoso lamagetsi.

6) Wiring. Mizere yolowera ndi yotulutsa mphamvu yamagetsi sayenera kuyikidwa pamphepete mwa bolodi la dielectric, apo ayi ndizosavuta kupanga ma radiation ndikusokoneza mabwalo ena kapena zida.

7) Mphamvu ya analogi ndi digito iyenera kulekanitsidwa. Zipangizo zamakono nthawi zambiri zimakhala zovuta kwambiri ku phokoso la digito, choncho ziwirizi ziyenera kulekanitsidwa ndikugwirizanitsa pamodzi pakhomo la magetsi. Ngati siginecha ikufunika kufalikira mbali zonse za analogi ndi digito, lupu imatha kuyikidwa pazizindikiro kuti muchepetse malo ozungulira. Monga momwe chithunzi 4 chikusonyezera.

Ikani lupu podutsa chizindikiro kuti muchepetse malo ozungulira

8) Pewani kuphatikizika kwa magetsi osiyana pakati pa zigawo zosiyanasiyana. Agwedezeni momwe mungathere, apo ayi phokoso lamagetsi limaphatikizidwa mosavuta kudzera mu mphamvu ya parasitic.

9) Patulani zigawo zokhudzidwa. Zigawo zina, monga zotsekera gawo (PLL), zimakhudzidwa kwambiri ndi phokoso lamagetsi. Asungeni kutali ndi magetsi momwe mungathere.

10) Ikani chingwe chamagetsi. Pofuna kuchepetsa phokoso la chizindikiro, phokoso likhoza kuchepetsedwa poyika chingwe chamagetsi pamphepete mwa mzere wa chizindikiro, monga momwe tawonetsera pa Chithunzi 5.

Ikani chingwe chamagetsi pafupi ndi mzere wa chizindikiro

11) Pofuna kupewa phokoso lamagetsi kuti lisasokoneze gulu la dera komanso phokoso lomwe linasokonekera chifukwa cha kusokoneza kwakunja kwa magetsi, bypass capacitor imatha kulumikizidwa pansi panjira yosokoneza (kupatula ma radiation), kuti phokosolo likhoza kudutsidwa pansi kuti lisasokoneze zipangizo ndi zipangizo zina.

Phokoso lamagetsi limapangidwa mwachindunji kapena mwanjira ina kuchokera kumagetsi ndipo limasokoneza dera. Popondereza zotsatira zake pa dera, mfundo yaikulu iyenera kutsatiridwa. Kumbali imodzi, phokoso lamagetsi liyenera kupewedwa momwe zingathere. Chikoka cha dera, kumbali ina, chiyeneranso kuchepetsa mphamvu ya dziko lakunja kapena dera pamagetsi, kuti lisawononge phokoso la magetsi.