Isibali Sokumelana Nokulandeleka Kwe-PCB: Indlela Yokubala Ukumelana Nokulandeleka Nokwehla Kwe-Voltage

Njalo copper trace has resistance, causing voltage drop and heating that can quietly undermine a good design. A trace resistance calculator turns width, copper thickness, length, and temperature into the actual ohms a trace adds. This guide answers the real questions – how to calculate PCB trace resistance, the resistance of 1 oz copper, how to cut it down – and shows how Highleap Electronics makes sure the trace you draw is the trace it builds.

1. Ubala kanjani ukumelana nokulandelela kwe-PCB?

Bala ukumelana kwe-PCB trace nge-R = ρ × ubude ÷ (ububanzi × ubukhulu), noma ngaphezulu mane nje uphindaphinde ukumelana kweshidi lethusi ngenani lezikwele (ubude ÷ ububanzi). Zombili zinikeza impendulo efanayo - indlela yezikwele ishesha kakhulu. Ukumelana ρ kuyinto engaguquki yezinto zethusi (cishe ama-1.7 × 10⁻⁸ ohm-metres ekushiseni kwegumbi), futhi indawo enqamulayo ububanzi buphindwe ubukhulu bethusi.

Isinqamuleli sezikwele sifanelekile ukujwayelaniswa: ukumelana kweshidi kuncike kuphela ekujikeni kwethusi, inani lezikwele limane nje ubude buhlukaniswe ububanzi, ngakho-ke:

Ukumelana nokulandelela ≈ ukumelana neshidi × (ubude ÷ ububanzi)

Yingakho i-trace ende, emincane inokumelana okuphezulu kanti emfushane, ebanzi inokumelana okuphansi - futhi kungani ukuphinda kabili isisindo sethusi (1 oz kuya ku-2 oz) cishe kuyingxenye yokumelana, ngoba ingxenye enqamulayo iphinda kabili. Ngakho-ke isisindo sethusi siyi-lever eyinhloko, yingakho imiklamo yamandla ifinyelela i- PCB yethusi esindayo lapho ukumelana kufanele kwehle. Ukuvuselelwa kokuthi i-trace ye-PCB isebenza kanjani kwenza okunye kube lula ukukusebenzisa.

2. Kuyini ukumelana komkhondo wethusi ongu-1 oz?

Ithusi elingu-1 oz linokumelana kweshidi okungaba ngu-0.5 milliohm ngesikwele, ngakho-ke i-trace ende ngokuphindwe kayishumi kunobubanzi bayo (izikwele eziyishumi) cishe ingama-milliohm ama-5 ngaphambi kokushisa kanye nemiphumela. Ithusi elijiyile liyakwehlisa lokhu ngokulinganayo - ithusi elingu-2 oz lingaba ngu-0.25 milliohm ngesikwele - ngoba ukumelana kuhambelana nendawo enqamulayo.

“Izikwele” ziyisilinganiso esingenamayunithi (ubude buhlukaniswe ngobubanzi), yingakho inombolo efanayo yokumelana neshidi isebenza kunoma yimuphi umkhondo kuleso sisindo sethusi. Ukuze uthole kusuka ezikweleni kuya kuma-ohms, phindaphinda ngokumelana neshidi kwethusi lakho; ukuze uthole kusuka kuma-ohms kuya ekwehleni kwe-voltage noma ekushiseni, faka ugesi. Leso sibalo sokumelana neshidi elilodwa, esihambisana nenani lezikwele, sanele ukulinganisa okusheshayo okuqhuba izinqumo eziningi zokwakheka.

3. Isibonelo esisebenzayo: ukumelana nokulandelela, ukwehla kwamandla kagesi, kanye namandla

Kumkhondo ongu-50 mm ubude, ongu-0.5 mm ububanzi ku-1 oz yethusi ephethe u-2 A, ukumelana kungaba ngu-50 milliohms, ukwehla kwamandla kagesi kungu-100 mV, kanti amandla ahlakazekile angu-0.2 W. Nasi isibalo esiphelele:

• Izikwele: ubude ÷ ububanzi = 50 ÷ 0.5 = izikwele eziyi-100.
• ukumelana: Izikwele eziyi-100 × ~0.5 mΩ/isikwele ≈ ama-milliohms angu-50.
• Ukwehla kwamandla kagesi: ukumelana × ugesi = 0.050 Ω × 2 A = 0.1 V (100 mV).
• Amandla aphelile: amandla amanje² × ukumelana = 2² × 0.050 = 0.2 W yokushisa.

Ku-rail engu-3.3 V, ukwehla kwe-100 mV cishe kungu-3% - ngokuvamile kuyamukeleka, ngezinye izikhathi akwamukeleki. Manje yandisa umugqa ube ngu-2 mm: izikwele zehla zibe ngu-25, ukumelana kube ngu-12.5 mΩ, ukwehla kwe-voltage kube ngu-25 mV. Umugqa obanzi ngokuphindwe kane unikeza ukumelana okuphansi ngokuphindwe kane - ukuhweba okuyinhloko okuvezwa yi-calculator, kanye nesinqumo okufanele sithathwe ngaphambi kokuba ukwakheka kuqedwe, hhayi ngemva kokuba ibhodi lishise kakhulu. Kuma-rail anomsinga ophezulu, ubunjiniyela obukhethekile bomthamo wamandla wamanje wethusi osindayo bugcina ukumelana nokushisa kubhekiwe.

4. Ingabe ukumelana kwe-trace kuyashintsha ngokushisa kanye nama-via?

Yebo – ukumelana kwethusi kukhuphuka cishe ngo-0.4% nge-°C ngayinye, ngakho-ke i-trace egijima ngo-40°C ngaphezu kwezinga lokushisa legumbi inokumelana okungaphezu kuka-16% kunenani layo lokubanda, futhi i-via ngayinye endleleni yengeza okunye okwengeziwe. Ngenxa yokuthi lokho kumelana okwengeziwe nakho kwenza ukushisa okwengeziwe, izinga lokushisa kanye nokumelana kuyaqina komunye nomunye ezindleleni ezishisayo, zamandla aphezulu. Okunye ukulungiswa komhlaba wangempela:

• Ukubekezelelana kwe-etch. Ukukhiqiza kunciphisa yonke iminonjana kancane uma kuqhathaniswa nalokho okudwebile, kuphakamisa ukumelana; ithusi elisindayo landisa lokhu kubekezelelana.
• I-Vias. Indlela egxuma phakathi kwezingqimba iqoqana ngokumelana, ngakho-ke kusetshenziswa ukuguqulwa kwamandla aphezulu ukuthululwa kwethusi nangokuthungwa ukwehlisa inani elihlanganisiwe.
• Ukubeka ipuleti. Ithusi eliqediwe elingaphandle lifaka phakathi i-plating, ngakho-ke ukujiya kwangempela kungadlula isisindo se-foil eyisisekelo.

Emsebenzini omningi, isilinganiso sezikwele zokushisa kwegumbi siseduze ngokwanele ukunquma; ngamandla aqinile noma imiklamo yokuzwa, hlanganisa izinga lokushisa futhi ubhekane nokumelana, ukuphathe njengengxenye yokuphathwa kokushisa kwe-PCB iyonke.

5. Indlela yokunciphisa ukumelana nokulandelela kwe-PCB

Nciphisa ukumelana nokulandela umkhondo ngokwandisa umkhondo, usebenzisa ithusi elisindayo, unciphise indlela, ushintshe amanethi kagesi abe yithusi elithululwayo noma indiza, bese ulinganisa ama-via lapho kushintsha ungqimba. I-lever ngayinye isebenza ngoba ukumelana kufana nokumelana neshidi izikhathi eziyizikwele: yandisa noma iqine ukuze wengeze isigaba esiphambeneyo, mfushane ukuze unqume izikwele. Ngokulandelana komthelela:

• Ithusi elinzima – 2 oz noma 3 oz usika ukumelana ngokulinganayo ngobubanzi obufanayo.
• Imigqa ebanzi noma ukuthulula – indiza empeleni iyisiqhubi esikhulu kakhulu, esingakwazi ukumelana kakhulu.
• Umzila omfushane – izikwele ezimbalwa, ukumelana nokuwa okuncane.
• Ama-via ahambisanayo – ama-vias amaningi ekushintsheni kwesendlalelo ahlukanisa ukumelana kwe-via.

Lapho izimpawu zishesha khona kunokuba zibe namandla aphezulu, isigaba esihlobene naso yi -impedance elawulwayo kunokumelana - inhloso ehlukile, izibalo ezahlukene.

6. Ingabe ukumelana kuzohlala ngemva kokwenziwa?

Ukumelana okubalwa kuyasebenza kuphela uma umkhondo wenziwe ngobukhulu obucatshangelwe, futhi ukugoba kanye nokufaka iplati kushintsha inani eliqediwe kancane - ngokuvamile okuncane, kodwa kwanele ukuba nendaba ngesabelomali samandla amancane noma umkhondo othembele kuwo njengenani eliqondile. Uma ububanzi bubalulekile, qinisekisa inhloso yomklamo nomenzi wakho.

Ukuhlolwa kokuklama kokukhiqiza ngaphambi kokwakha kuqinisekisa ukuthi ukulandelwa kwamandla akho, isisindo sethusi, kanye nesu lakho kuyenzeka nokuthi i-geometry eqediwe ifika lapho uyidinga khona. I-Highleap ibe isithwala ibhodi ngokusebenzisa ukwenziwa nokuhlanganiswa kwethusi elijiyile , ngezinketho zethusi elisindayo zezindlela zamandla ezimelana nokumelana okuphansi kanye nokulinganisa kwesihloko sokuqala lapho umklamo uncike ekumelaneni okuthile kokulandelwa noma ukwehla kwamandla. Uma ucela intengo, faka isisindo sethusi, imigqa lapho ukwehla kwamandla kubalulekile khona, kanye nanoma yimuphi umkhondo othembele kuwo ukumelana kwawo.

Caphuna ibhodi lami lamandla

7. Imibuzo Evame Ukubuzwa Yokumelana Nokulandelela

Ubala kanjani ukumelana nokulandelela kwe-PCB?

Sebenzisa u-R = ρ × ubude ÷ (ububanzi × ubukhulu), noma uphindaphinde ukumelana kweshidi lethusi (cishe u-0.5 mΩ/isikwele ku-1 oz) ngenani lezikwele (ubude ÷ ububanzi). Zombili zinikeza umphumela ofanayo.

Kuyini ukumelana komkhondo wethusi ongu-1 oz?

Cishe i-0.5 milliohm ngesikwele. Ngakho-ke, i-trace ende ngokuphindwe kayishumi kunobubanzi bayo cishe ingama-5 mΩ ku-1 oz yethusi, ngaphambi kokushisa kanye nemiphumela.

Ingabe ukumelana kwe-trace kuyashintsha ngokushisa?

Yebo. Ukumelana nethusi kukhuphuka cishe ngo-0.4% nge-°C, ngakho-ke i-trace egijima kahle ngaphezu kwezinga lokushisa legumbi inokumelana okuphezulu kakhulu kunenani layo lokubanda.

Ngingakunciphisa kanjani ukumelana nokulandelela?

Yandisa umkhondo, sebenzisa ithusi elinzima, nciphisa indlela, sebenzisa ithusi elithululwayo noma iplani yamandla, kanye nama-via amaningi ahambisanayo ekushintsheni kwezendlalelo.

Ingabe i-Highleap ingakha amabhodi kagesi aqinile futhi aqinile, amelana nokumelana okuphansi?

Yebo. I-Highleap inikeza ithusi elisindayo lezindlela zamandla eziphansi ukumelana, ngamasu okushintsha kwezendlalelo, kanye nokulinganisa kwesihloko sokuqala lapho umklamo uncike ekumelaneni okuthile kokulandelela noma ukwehla kwamandla kagesi.