Lura da abubuwan la'akari masu zuwa don agogon kan allo:
1. Layout
a, kristal agogo da da'irori masu alaƙa yakamata a shirya su a tsakiyar matsayi na PCB kuma suna da kyakkyawan tsari, maimakon kusa da ƙirar I/O. Ba za a iya sanya da'irar tsara agogo ta zama katin 'ya mace ko sigar allo 'yar ba, dole ne a yi shi akan allon agogo daban ko allon jigilar kaya.
Kamar yadda aka nuna a cikin adadi mai zuwa, ɓangaren akwatin kore na Layer na gaba yana da kyau kada kuyi tafiya cikin layi
b, kawai na'urorin da ke da alaƙa da da'irar agogo a cikin yankin da'ira na agogo na PCB, kauce wa shimfiɗa wasu da'irori, kuma kada ku sanya wasu layukan sigina kusa ko ƙasa da crystal: Yin amfani da jirgin ƙasa a ƙarƙashin kewayawar agogo ko crystal, idan wasu sigina na wucewa ta cikin jirgin, wanda ya keta tsarin aikin jirgin sama, idan siginar ta ratsa ta cikin jirgin ƙasa, za a sami ɗan ƙaramin madauki na ƙasa kuma ya shafi ci gaba da jirgin ƙasa, kuma waɗannan madaukai na ƙasa za su haifar da matsala a lokuta masu yawa.
c. Don lu'ulu'u na agogo da da'irori na agogo, ana iya ɗaukar matakan kariya don sarrafa garkuwa;
d, idan harsashi agogon ƙarfe ne, ƙirar PCB dole ne a ɗora shi a ƙarƙashin jan ƙarfe na crystal, kuma a tabbatar da cewa wannan ɓangaren da cikakken jirgin ƙasa yana da haɗin wutar lantarki mai kyau (ta hanyar porous ƙasa).
Fa'idodin shimfidawa a ƙarƙashin lu'ulu'u na agogo:
Da'irar da ke cikin oscillator kristal tana haifar da halin yanzu na RF, kuma idan an rufe kristal a cikin gidaje na ƙarfe, fil ɗin wutar DC shine dogaro da ma'aunin wutar lantarki na DC da madaidaicin madauki na RF a cikin kristal, yana sakin madaidaicin halin yanzu wanda RF radiation na gidaje ta hanyar jirgin sama. A taƙaice, harsashi na ƙarfe eriya ce mai ƙarewa ɗaya, kuma hoton hoton da ke kusa, Layer jirgin ƙasa da wani lokacin yadudduka biyu ko fiye sun wadatar don haɗa haɗin RF na yanzu zuwa ƙasa. Ƙasar crystal kuma yana da kyau don zubar da zafi. Da'irar agogo da kristal da ke ƙasa za su samar da jirgin taswira, wanda zai iya rage yanayin gama gari da ke haifar da da'irar crystal da agogo mai alaƙa, don haka rage hasarar RF. Jirgin ƙasa kuma yana ɗaukar yanayin halin yanzu na RF na banbanta. Dole ne a haɗa wannan jirgin zuwa cikakken jirgin ƙasa ta maki da yawa kuma yana buƙatar ramuka da yawa, wanda zai iya samar da ƙananan ƙarancin. Don haɓaka tasirin wannan jirgin sama na ƙasa, kewayawar janareta na agogo yakamata ya kasance kusa da wannan jirgin ƙasa.
Lu'ulu'u masu kunshe da Smt za su sami ƙarin hasken wutar lantarki na RF fiye da lu'ulu'u masu sanye da ƙarfe: Saboda lu'ulu'u masu ɗorewa galibi fakitin filastik ne, RF na yanzu a cikin crystal zai haskaka sararin samaniya kuma haɗe zuwa wasu na'urori.
1. Raba tsarin agogo
Yana da kyau a haɗa sigina mai tasowa mai sauri da siginar kararrawa tare da radial topology fiye da haɗa hanyar sadarwa tare da tushen tuƙi guda ɗaya, kuma kowace hanya yakamata a bi ta hanyar dakatar da matakan daidai gwargwadon halayenta.
2, buƙatun layin watsa agogo da shimfiɗa PCB
Ka'ida ta hanyar agogo: Shirya cikakken hoton jirgin sama a kusa da layin agogo, rage tsawon layin kuma aiwatar da sarrafa impedance.
Rashin daidaiton wayoyi na giciye da rashin daidaituwa na iya haifar da:
1) Yin amfani da ramuka da tsalle a cikin wayoyi suna haifar da rashin mutunci na madauki na hoto;
2) Ƙimar wutar lantarki a kan hoton hoton saboda wutar lantarki a kan siginar siginar na'urar yana canzawa tare da canjin siginar;
3), idan layin bai yi la'akari da ka'idar 3W ba, siginonin agogo daban-daban zasu haifar da crosstalk;
Wayar da siginar agogo
1, layin agogo dole ne yayi tafiya a cikin Layer na ciki na allon PCB mai yawan Layer. Kuma tabbatar da bin layin kintinkiri; Idan kuna son yin tafiya a saman Layer na waje, layin microstrip kawai.
2, Layer na ciki na iya tabbatar da cikakken jirgin sama na hoto, yana iya samar da hanyar watsawa ta RF mara ƙarfi, kuma yana haifar da jujjuyawar maganadisu don daidaita jigilar magnetic na layin watsa tushen su, kusancin nesa tsakanin tushen da hanyar dawowa, mafi kyau da degaussing. Godiya ga haɓakar haɓakar lalata, kowane cikakken shirin hoto na PCB mai girma yana ba da ɓata 6-8dB.
3, abũbuwan amfãni daga Multi-Layer jirgin: akwai wani Layer ko mahara yadudduka za a iya sadaukar da cikakken wutar lantarki da jirgin sama, za a iya tsara a cikin mai kyau decoupling tsarin, rage yankin na ƙasa madauki, rage bambanci yanayin. radiation, rage EMI, rage matakin impedance na siginar da kuma hanyar dawowar wutar lantarki, zai iya kula da daidaiton dukkanin layin layi, rage raguwa tsakanin layin da ke kusa.
Lokacin aikawa: Jul-05-2023
