A cikin zane, shimfidawa shine muhimmin sashi.Sakamakon shimfidar wuri zai shafi tasirin wayoyi kai tsaye, don haka zaku iya tunanin shi ta wannan hanyar, shimfidar wuri mai ma'ana shine matakin farko na nasarar ƙirar PCB.
Musamman, riga-kafi shine tsarin tunani game da dukkanin jirgi, siginar sigina, zubar da zafi, tsari da sauran gine-gine.Idan tsarin da aka riga aka tsara ya gaza, ƙarin ƙoƙari na baya shima a banza ne.
1. Yi la'akari da duka
Nasarar samfurin ko a'a, ɗaya shine don mayar da hankali ga ingancin ciki, na biyu shine la'akari da kyawawan kayan ado, duka biyu sun fi dacewa don la'akari da samfurin yana da nasara.
A kan allo na PCB, shimfidar abubuwan da ake buƙata don daidaitawa, raɗaɗi da tsari, ba mai nauyi ko kai mai nauyi ba.
Shin PCB zata lalace?
An ajiye gefuna na tsari?
An tanada maki MARK?
Shin wajibi ne a haɗa allon?
Nawa yadudduka na hukumar, za su iya tabbatar da sarrafa impedance, garkuwar sigina, amincin siginar, tattalin arziki, cimma nasara?
2. Ware ƙananan kurakurai
Girman allo da aka buga yayi daidai da girman zanen sarrafawa?Za a iya saduwa da PCB masana'antu tsari bukatun?Akwai alamar matsayi?
Abubuwan da ke cikin sararin samaniya mai girma biyu, mai girma uku babu rikici?
Shin tsarin kayan aikin yana cikin tsari kuma an tsara shi da kyau?An gama duk kayan?
Za a iya maye gurbin abubuwan da ake buƙatar musanya akai-akai cikin sauƙi?Shin ya dace don saka allon sakawa a cikin kayan aiki?
Shin akwai tazarar da ta dace tsakanin ma'aunin zafin jiki da na'urar dumama?
Shin yana da sauƙi don daidaita abubuwan daidaitacce?
An shigar da matattarar zafi inda ake buƙatar zubar da zafi?Shin iska tana gudana ba tare da wata matsala ba?
Shin siginar yana gudana santsi kuma mafi guntuwar haɗin kai?
Shin matosai, kwasfa, da sauransu sun saba wa ƙirar injina?
Shin ana la'akari da matsalar kutse na layin?
3. Bypass ko decoupling capacitor
A cikin wayoyi, na'urorin analog da na dijital suna buƙatar waɗannan nau'ikan capacitors, suna buƙatar kusanci da fitilun wutar lantarki da aka haɗa zuwa madaidaicin kewayawa, ƙimar capacitance yawanci 0.1μF. fil a takaice gwargwadon yiwu don rage juriya na inductive na jeri, kuma kusa da na'urar.
Ƙara kewaye ko decoupling capacitors a cikin allo, da kuma sanya waɗannan capacitors a kan allo, shine ilimin asali na dijital da analog, amma ayyukansu sun bambanta.Sau da yawa ana amfani da capacitors na keɓancewa a ƙirar wayoyi na analog don ketare sigina masu tsayi daga wutar lantarki wanda in ba haka ba zai iya shigar da kwakwalwan kwamfuta masu mahimmanci ta hanyar fitilun samar da wutar lantarki.Gabaɗaya, mitar waɗannan sigina masu ƙarfi sun zarce ƙarfin na'urar analog don murkushe su.Idan ba a yi amfani da capacitors na kewaye ba a cikin da'irori na analog, amo da kuma, a cikin mafi tsanani lokuta, za a iya gabatar da rawar jiki a cikin hanyar sigina.Don na'urorin dijital kamar masu sarrafawa da masu sarrafawa, ana kuma buƙatar decoupling capacitors, amma saboda dalilai daban-daban.Ɗaya daga cikin ayyukan waɗannan capacitors shine yin aiki a matsayin banki na cajin "ƙananan", saboda a cikin da'irori na dijital, yin canjin yanayin ƙofar kofa (watau sauyawa) yawanci yana buƙatar adadi mai yawa na halin yanzu, kuma lokacin da ake canza transients akan guntu da gudana. ta hanyar allo, yana da fa'ida don samun wannan ƙarin cajin "sare".” cajin yana da fa'ida.Idan babu isasshen caji don aiwatar da aikin sauyawa, zai iya haifar da babban canji a wutar lantarki.Babban canjin wutar lantarki na iya haifar da matakin siginar dijital ya shiga cikin yanayi mara iyaka kuma yana iya haifar da na'urar jihar a cikin na'urar dijital tayi aiki da kuskure.Canjin canjin da ke gudana ta hanyar daidaita allo zai sa wutar lantarki ta canza, saboda inductance na parasitic na daidaitawar allo, ana iya ƙididdige canjin wutar lantarki ta amfani da dabara mai zuwa: V = Ldl/dt inda V = canjin ƙarfin lantarki L = allo. alignment inductance dI = canji a halin yanzu yana gudana ta hanyar daidaitawa dt = lokacin canji na yanzu Don haka, saboda dalilai daban-daban, wutar lantarki a wutar lantarki ko na'urori masu aiki a fitilun wutar lantarki da aka yi amfani da su ta hanyar wucewa (ko decoupling) capacitors suna da kyakkyawan aiki. .
Mai shigar da wutar lantarki, idan halin yanzu yana da girma, ana bada shawara don rage tsayi da yanki na daidaitawa, kada ku gudu a duk faɗin filin.
Hayaniyar sauyawa akan shigarwar da aka haɗa da jirgin sama na fitarwar wutar lantarki.Hayaniyar sauyawa na bututun MOS na samar da wutar lantarki yana rinjayar shigar da wutar lantarki na matakin gaba.
Idan akwai babban adadin babban DCDC na yanzu a kan allo, akwai mitoci daban-daban, tsangwama mai tsayi da babban ƙarfin lantarki.
Don haka muna buƙatar rage yanki na shigar da wutar lantarki don saduwa da abubuwan da ke faruwa a yanzu.Don haka lokacin shimfidar wutar lantarki, yi la'akari da guje wa shigar da wutar lantarki cikakken allon allo.
4. Layin wutar lantarki da ƙasa
Layukan wuta da layukan ƙasa suna da kyau wurin daidaitawa, na iya rage yuwuwar kutsawar wutar lantarki (EMl).Idan wutar lantarki da layin ƙasa ba su dace da kyau ba, za a tsara madaidaicin tsarin, kuma yana iya haifar da hayaniya.An nuna misalin wutar lantarki da ba ta dace ba da ƙirar PCB na ƙasa a cikin adadi.A cikin wannan allo, yi amfani da hanyoyi daban-daban don yafa wuta da ƙasa, saboda wannan rashin dacewa, kayan aikin lantarki da layukan hukumar ta hanyar tsoma baki (EMI) sun fi dacewa.
5. Digital-analog rabuwa
A cikin kowane zane na PCB, sashin amo na kewaye da sashin "shiru" (bangaren mara hayaniya) da za a rabu.Gabaɗaya, da'irar dijital na iya jure wa tsangwama a cikin amo, kuma ba ta kula da amo (saboda da'irar dijital tana da babban juriyar amo);akasin haka, haƙurin hayaniyar da'irar wutar lantarki ta analog ya fi karami.Daga cikin biyun, da'irori na analog sun fi dacewa da sauya amo.A cikin tsarin siginar haɗaɗɗiyar wayoyi, waɗannan nau'ikan da'irori guda biyu yakamata a raba su.
Abubuwan da ake amfani da su na wayoyi na allon kewayawa sun shafi duka na'urorin analog da na dijital.Babban ƙa'idar babban yatsan hannu shine amfani da jirgin ƙasa mara yankewa.Wannan ƙa'ida ta asali tana rage tasirin dI/dt (a halin yanzu da lokaci) a cikin da'irori na dijital saboda tasirin dI/dt yana haifar da yuwuwar ƙasa kuma yana ba da damar hayaniya ta shiga da'irar analog.Dabarun wayoyi don da'irori na dijital da analog iri ɗaya ne, sai dai abu ɗaya.Wani abu da za a tuna don da'irori na analog shine kiyaye layukan siginar dijital da madaukai a cikin jirgin ƙasa kamar nisa daga da'irar analog kamar yadda zai yiwu.Ana iya cimma wannan ta hanyar haɗa jirgin sama na analog daban zuwa haɗin ƙasa na tsarin, ko kuma ta hanyar sanya da'ira na analog a ƙarshen allo, a ƙarshen layin.Ana yin wannan don kiyaye tsangwama daga waje zuwa mafi ƙarancin hanyar sigina.Wannan ba lallai ba ne don da'irori na dijital, wanda zai iya jure wa yawan hayaniya a kan jirgin ƙasa ba tare da matsala ba.
6. Thermal la'akari
A cikin tsarin shimfidawa, buƙatar yin la'akari da raƙuman iska mai zafi, zafi mai zafi ya ƙare.
Kada a sanya na'urori masu zafin zafi a bayan iskar tushen zafi.Ba da fifiko ga shimfidar wuri na irin wannan gidan mai wahala mai wahala kamar DDR.Guji maimaita gyare-gyare saboda thermal simulation baya wucewa.
Lokacin aikawa: Agusta-30-2022