Tikamapanga PCB, nthawi zambiri timadalira zomwe takumana nazo komanso maluso omwe nthawi zambiri timapeza pa intaneti. Aliyense kapangidwe PCB akhoza wokometsedwa ntchito inayake. Nthawi zambiri, malamulidwe ake amangogwiritsidwa ntchito pazolinga zomwe mukufuna. Mwachitsanzo, malamulo a ADC PCB samagwira ntchito ku ma PCB a RF komanso mosemphanitsa. Komabe, malangizo ena angawonekere ngati mapangidwe a PCB iliyonse. Apa, mu phunziroli, tidziwitsa zovuta zina ndi maluso omwe atha kusintha ma PCB.
Kugawa magetsi ndichinthu chofunikira kwambiri pakapangidwe kalikonse ka magetsi. Zida zanu zonse zimadalira mphamvu kuti ichite bwino. Kutengera kapangidwe kanu, zinthu zina zimatha kulumikizana ndi magetsi osiyanasiyana, pomwe zinthu zina pa bolodi lomwelo zimatha kulumikizana ndi magetsi. Mwachitsanzo, ngati zinthu zonse zimayendetsedwa ndi kachingwe kamodzi, chigawo chilichonse chimawona zovuta zina, zomwe zimabweretsa maumboni angapo. Mwachitsanzo, ngati muli ndi madera awiri a ADC, amodzi koyambirira ndi ena kumapeto, ndipo ma ADC onse amawerenga mphamvu yakunja, dera lililonse la analog liziwerenga zosiyana zomwe zingafanane nawo.
Titha kufotokozera mwachidule kugawa kwamagetsi m’njira zitatu: mfundo imodzi, gwero la Star ndi gwero la multipoint.
(a) Malo amagetsi amodzi: magetsi ndi waya wapansi pachinthu chilichonse amasiyana. Kuyendetsa mphamvu kwa zigawo zonse kumangokumana pamalo amodzi. Mfundo imodzi imawerengedwa kuti ndi yoyenera mphamvu. Komabe, izi sizingatheke pulojekiti zovuta kapena zazikulu / zapakatikati.
(b) Gwero la nyenyezi: Gwero la Star limatha kutengedwa ngati kusintha kwa gwero limodzi. Chifukwa cha mawonekedwe ake ofunikira, ndizosiyana: kutalika kwa mayendedwe pakati pazinthu ndizofanana. Kulumikizana kwa nyenyezi nthawi zambiri kumagwiritsidwa ntchito pama board azizindikiro othamanga kwambiri okhala ndi mawotchi osiyanasiyana. Mu PCB yothamanga kwambiri, chizindikirocho nthawi zambiri chimachokera m’mphepete kenako chimafika pakatikati. Zizindikiro zonse zimatha kufalikira kuchokera pakati kupita kudera lililonse la bolodi, ndipo kuchedwa pakati pamadera kumatha kuchepetsedwa.
(c) Magwero azinthu zambiri: amawoneka ngati osauka mulimonsemo. Komabe, ndizosavuta kugwiritsa ntchito mdera lililonse. Magwero azinthu zambiri amatha kupanga kusiyanasiyana pakati pazinthu komanso kulumikizana kwama impedance. Mtundu wamapangidwe woterewu umathandiziranso kusintha kwa IC, wotchi ndi ma circuits a RF kuti apange phokoso m’maseketi oyandikana nawo omwe amagawana kulumikizana.
Zachidziwikire, m’moyo wathu watsiku ndi tsiku, sitikhala ndi mtundu umodzi wogawa nthawi zonse. Tradeoff yomwe tingapange ndikuphatikiza magwero amodzi ndi magwero angapo. Mutha kuyika zida zodziwika bwino za analog ndi makina othamanga kwambiri / RF munthawi imodzi, ndi zida zina zonse zosazindikira nthawi imodzi.
Kodi mudaganizapo ngati mungagwiritse ntchito ndege zamagetsi? Yankho ndilo inde. Bokosi lamagetsi ndi njira imodzi yosamutsira mphamvu ndikuchepetsa phokoso la dera lililonse. Ndege yamagetsi imafupikitsa njira yolowera pansi, imachepetsa kuchepa komanso imathandizira magwiridwe antchito amagetsi (EMC). Zimakhalanso chifukwa chakuti mbale yofananira yolumikizira yomwe imapangidwanso imapanganso ndege zamagetsi mbali zonse ziwiri, kuti tipewe kufalikira kwa phokoso.
Bolodi yamagetsi ilinso ndi mwayi wowonekera: chifukwa cha malo ake akulu, imalola zambiri zaposachedwa, motero kuwonjezera kutentha kwa magwiridwe antchito a PCB. Koma chonde dziwani: wosanjikiza wamagetsi amatha kusintha magwiridwe antchito, koma zingwezo ziyenera kuganiziridwanso. Malamulo otsata amaperekedwa ndi ipc-2221 ndi ipc-9592
Kuti mupeze PCB yokhala ndi chida cha RF (kapena kugwiritsa ntchito siginecha yothamanga kwambiri), muyenera kukhala ndi ndege yathunthu yokwaniritsa magwiridwe antchito a board. Zizindikirozo ziyenera kukhala pa ndege zosiyanasiyana, ndipo ndizosatheka kukwaniritsa zofunikira zonsezo nthawi imodzi pogwiritsa ntchito zigawo ziwiri za mbale. Ngati mukufuna kupanga tinyanga kapena bolodi lililonse lovuta la RF, mutha kugwiritsa ntchito magawo awiri. Chithunzi chotsatira chikuwonetsa fanizo momwe PCB yanu ingagwiritsire ntchito bwino ndegezi.
Mumapangidwe osakanikirana, opanga nthawi zambiri amalimbikitsa kuti nthaka ya analogi isiyanitsidwe ndi digito. Maseketi anzeru amakhudzidwa mosavuta ndimasinthidwe othamanga ndi zizindikilo. Ngati kukhazikika kwa analog ndi digito kuli kosiyana, ndegeyo idzapatulidwa. Komabe, ili ndi zovuta zotsatirazi. Tiyenera kusamala ndi crosstalk ndi loop m’dera logawanika lomwe limayambitsidwa makamaka ndikutha kwa ndege yapansi. Fanizo lotsatirali likuwonetsa chitsanzo cha ndege ziwiri zapansi. Kudzanja lamanzere, mphamvu yobwerera siyingadutse molunjika njira yolozera, chifukwa chake padzakhala malo ozungulira m’malo mokonzedwa moyenera.
Kugwirizana kwamagetsi ndi kusokoneza kwamagetsi (EMI)
Pakapangidwe kazambiri (monga ma RF), EMI ikhoza kukhala vuto lalikulu. Ndege yapansi yomwe takambirana kale imathandizira kuchepetsa EMI, koma malinga ndi PCB yanu, ndegeyo ingayambitse mavuto ena. Mu laminates okhala ndi zigawo zinayi kapena kupitilira apo, mtunda wa ndege ndikofunikira kwambiri. Capacitance pakati pa ndege ndiyochepa, gawo lamagetsi limakulitsa pa bolodi. Nthawi yomweyo, kusokonekera pakati pa ndege ziwiri kumachepa, kulola kuti kubwerera kubwerere ku ndege yolozera. Izi zipanga EMI pazizindikiro zilizonse zodutsa ndege.
Njira yosavuta yopewa EMI ndikuletsa mayendedwe othamanga kuti asadutse magawo angapo. Onjezani decoupling capacitor; Ndipo ikani ma vias mozungulira zingwe zamagetsi. Chithunzi chotsatirachi chikuwonetsa kapangidwe kabwino ka PCB kokhala ndi chizindikiritso chapamwamba.
Sefani phokoso
Ma Bypass capacitors ndi mikanda ya ferrite ndi ma capacitors omwe amagwiritsidwa ntchito kusefa phokoso lomwe limapangidwa ndi chinthu chilichonse. Kwenikweni, ngati imagwiritsidwa ntchito pulogalamu yothamanga kwambiri, pini iliyonse ya I / O imatha kukhala phokoso. Kuti tigwiritse ntchito bwino izi, tiyenera kulabadira mfundo izi:
Nthawi zonse ikani mikanda ya ferrite ndikudutsa ma capacitors pafupi kwambiri ndi phokoso.
Tikamagwiritsa ntchito njira zodziwikiratu komanso njira zodziwikira zokha, tiyenera kulingalira mtunda wowunika.
Pewani vias ndi njira ina iliyonse pakati pa zosefera ndi zinthu zina.
Ngati pali ndege yapansi, gwiritsani ntchito angapo kudzera m’mabowo kuti muigwetse molondola.