1. General tsika
MuPCB dhizaini, kuitira kuti iite yakakwira frequency redunhu dhizaini dhizaini, zvirinani anti-kukanganisa kuita, inofanirwa kutariswa kubva kune zvinotevera zvinhu:
(1) Kusarudzwa kunonzwisisika kwezvikamu Paunenge uchifambisa-high-frequency circuit boards muPCB design, ndege yemukati iri pakati inoshandiswa sesimba uye pasi pasi, iyo inogona kuita basa rekudzivirira, zvinobudirira kuderedza parasitic inductance, kupfupisa kureba. mitsetse yechiratidzo, uye kuderedza kupindira kwemuchinjikwa pakati pezviratidzo.
(2) Routing mode Routing mode inofanirwa kuenderana ne45 ° Angle kutendeuka kana arc kutendeuka, iyo inogona kuderedza yakakwira-frequency chiratidzo chekuburitsa uye kuwirirana kubatana.
(3) Cable urefu Kupfupika kwetambo kureba, zviri nani.Iyo ipfupi nhambwe yakaenzana pakati pewaya mbiri, zviri nani.
(4) Huwandu hwemaburi Hushoma huwandu hwemaburi, zviri nani.
(5) Interlayer wiring direction Iyo nzira ye interlayer wiring inofanira kuva yakatwasuka, kureva kuti, chikamu chepamusoro chakatwasuka, chepasi chakamira, kuitira kuderedza kupindira pakati pezviratidzo.
(6) Copper coating yakawedzera kugadzika copper coating inogona kuderedza kupindirana pakati pezviratidzo.
(7) Kubatanidzwa kweiyo yakakosha mutsara mutsara wekugadzirisa, inogona kuvandudza zvakanyanya kupesana-kupindira kugona kwechiratidzo, hongu, inogonawo kuve kubatanidzwa kwekupindira kweiyo sosi yekugadzirisa, kuitira kuti irege kupindira nezvimwe zviratidzo.
(8) Chiratidzo tambo hadzifambisi masaini muzvishwe.Masaini enzira muDaisy chain mode.
2. Wiring pokutanga
Kiyi yechiratidzo mutsara wakakosha: analogi diki chiratidzo, yakakwira-kumhanya chiratidzo, wachi uye chiratidzo chekuyananisa uye mamwe makiyi masaini ekutanga wiring.
Density yekutanga musimboti: Tanga wiring kubva kune yakanyanya kuomesesa yekubatanidza pabhodhi.Tanga wiring kubva kune yakanyanya densely wired nzvimbo yebhodhi
Pfungwa dzekucherechedza:
A. Edza kupa yakakosha wiring layer yezviratidzo zvakakosha senge wachi, high-frequency signals uye sensitive signals, uye simbisai diki loop area.Kana zvichidikanwa, manyorero ekutanga wiring, kudzivirira uye kuwedzera kuchengetedza nzvimbo kunofanirwa kugamuchirwa.Iva nechokwadi chemhando yechiratidzo.
b.EMC nharaunda pakati pesimba remagetsi uye pasi haina kunaka, saka masaini anonzwa kukanganiswa anofanira kudzivirirwa.
c.Iyo network ine impedance control zvinodiwa inofanirwa kuve waya sezvinobvira zvichienderana nehurefu hwemutsara uye mutsara upamhi zvinodiwa.
3, waya wewachi
Mutsetse wewachi ndechimwe chezvinhu zvikuru zvinokanganisa EMC.Ita maburi mashoma mumutsara wewachi, dzivisa kufamba nemamwe mitsara yemasaini kusvika paunokwanisa, uye gara kure nemitsara yezviratidzo kuti udzivise kuvhiringwa nemitsara yemasaini.Panguva imwecheteyo, simba rekupa pabhodhi rinofanira kudziviswa kudzivirira kukanganisa pakati pemagetsi uye wachi.
Kana pane yakakosha wachi chip pabhodhi, haigoni kuenda pasi pemutsara, inofanira kuiswa pasi pemhangura, kana zvichidiwa, inogonawo kuva yakakosha kunyika yayo.Kune akawanda chip reference crystal oscillator, aya ekristaro oscillator haafaniri kunge ari pasi pemutsara, kuisa kuparadzaniswa kwemhangura.
4. Mutsetse pamakona akarurama
Right-angle cabling inowanzodiwa kudzivirira mamiriro ezvinhu muPCB wiring, uye yatove imwe yemayero ekuyera kunaka kwewaya, saka ingani mhedzisiro ichave nekona yekurudyi pakufambiswa kwechiratidzo?Muchidimbu, nzira yekurudyi-kona inokonzeresa hupamhi hwemutsara weiyo tambo yekutapurirana ichinje, zvichikonzera kuti impedance irege kuenderera.Muchokwadi, kwete chete kurudyi Angle routing, toni Angle, acute Angle routing inogona kukonzera impedance shanduko.
Kurudziro yekurudyi-kona nzira pachiratidzo inonyanya kuratidzwa muzvikamu zvitatu:
Kutanga, kona inogona kuenzana ne capacitive load pamutsetse wekutumira, inononoka nguva yekusimuka;
Chechipiri, impedance discontinuity ichakonzera chiratidzo chekuratidzira;
Chechitatu, EMI inogadzirwa neiyo kona yeAngle tip.
5. Acute Angle
(1) Kune yakakwira frequency yazvino, kana iyo yekutendeuka kwewaya ichipa kona yekurudyi kana kunyange acute Angle, padyo nekona, iyo magineti flux density uye simba remagetsi remumunda rinenge rakakwira, richaita radiation yakasimba electromagnetic wave, uye inductance. pano ichave yakakura, iyo inductive ichave yakakura kupfuura iyo obtuse Angle kana yakatenderedzwa Angle.
(2) Kune iyo bhasi wiring yedhijitari yedhijitari, iyo wiring kona inoputika kana yakatenderedzwa, nzvimbo yewaya idiki.Pasi pemutsetse wakafanana wepakati, mutsara wemitsara unotora kakapetwa ka0.3 pasi pehupamhi pane kona yekurudyi.
6. Yakasiyana nzira
Cf.Yakasiyana wiring uye impedance kuenzanisa
Differential Signal inoshandiswa zvakanyanya uye zvakanyanya mukugadzirwa kwepamusoro-kumhanya maseketi, nekuti iyo inonyanya kukosha masaini mumaseketi anogara anoshandisa akasiyana dhizaini.Tsanangudzo: MuchiRungu chakajeka, zvinoreva kuti mutyairi anotumira masaini maviri akaenzana, anotenderedza, uye anogamuchira anoona kana mamiriro ane musoro ari "0" kana "1" nekuenzanisa mutsauko pakati pemagetsi maviri.Vaviri vakatakura chiratidzo chekusiyanisa vanodaidzwa kunzi differential routing.
Kuenzaniswa neyakajairwa-inopera-inogumira chiratidzo routing, mutsauko wechiratidzo une mabhenefiti ari pachena mune matatu anotevera maficha:
a.Kugona kwakasimba kurwisa-kupindira, nekuti kubatanidzwa pakati pewaya mbiri dzekusiyanisa kwakanaka kwazvo, kana paine kupindira kweruzha kubva kunze, kunenge kwakabatana nemitsara miviri panguva imwe chete, uye mugamuchiri anongotarisira nezve musiyano pakati pe masaini maviri, saka iyo yakajairika modhi ruzha kubva kunze inogona kubviswa zvachose.
b.inogona kunyatso kuvharidzira EMI.Saizvozvo, nekuti polarity yezviratidzo zviviri zvakapesana, minda yemagetsi inovhenekerwa navo inogona kukanzura mumwe nemumwe.Iko kuswedera kwekubatanidza, kushoma kwesimba remagetsi rinoburitswa kune kunze kwenyika.
c.Nguva chaiyo yekumisikidza.Sezvo shanduko yekuchinja kwemasaini masaini ari pamharadzano yezviratidzo zviviri, kusiyana neakajairwa-anogumira masaini anovimba nepamusoro uye yakaderera chikumbaridzo voltage, kukanganisa kwetekinoroji uye tembiricha idiki, inogona kuderedza zvikanganiso mukufamba kwenguva uye zvakanyanya. akakodzera kumatunhu ane low amplitude zviratidzo.LVDS (yakaderera voltage kusiyanisa kusaina), iyo yakakurumbira parizvino, inoreva iyi diki amplitude yekusiyanisa kusaina tekinoroji.
Kune mainjiniya ePCB, chinhu chinonyanya kukosha ndechekuona kuti zvakanakira nzira yekusiyanisa inogona kushandiswa zvizere munzira chaiyo.Zvichida chero bedzi kusangana neLayout vanhu vachanzwisisa zvinodikanwa zvakajairika zvekusiyanisa nzira, ndiko kuti, "kuenzana kureba, kureba kwakaenzana".
Iyo yakaenzana kureba ndeyekuona kuti maviri akasiyana masaini anochengetedza akatarisana polarity nguva dzese uye kuderedza yakajairika-modhi chikamu.Equidistance inonyanya kuve nechokwadi chekuti mutsauko impedance inowirirana uye kuderedza kutarisisa."Sepedyo sezvinobvira" dzimwe nguva chinhu chinodiwa pakusiyanisa nzira.
7. Mutsara wenyoka
Serpentine mutsetse imhando yeRayout iyo inowanzo shandiswa mukurongeka.Chinangwa chayo chikuru ndechekugadzirisa kunonoka uye kusangana nezvinodiwa zvehurongwa hwekugadzirisa nguva.Chinhu chekutanga vagadziri vanofanirwa kuziva ndechekuti waya dzakaita senyoka dzinogona kuparadza mhando yechiratidzo uye kuchinja kunonoka kutapurirana, uye dzinofanirwa kudzivirirwa kana wiring.Zvisinei, mukugadzirwa kwechokwadi, kuitira kuti tive nechokwadi chekubata nguva yakakwana yezviratidzo, kana kuderedza nguva yekugadzirisa pakati peboka rimwechete rezviratidzo, zvinowanzodiwa mhepo nemaune.
Pfungwa dzekucherechedza: