Everyone knows doing the principle diagram of the PCB is designed into a real piece of PCB, please don’t look down upon this process, there are a lot of things on the principle of practicable in engineering has difficult to achieve, or something that someone can achieve them,but others can not, so it is not difficult to make a PCB, but make a good PCB ibhodi akuyona into elula.
Nobunzima ezimbili ezinkulu emkhakheni Microelectronics yilona eliphezulu isignali imvamisa futhi ebuthaka signal processing, PCB ukukhiqizwa ezingeni kubalulekile ikakhulukazi kulesi sici, umklamo ofanayo isimiso, yezingxenye efanayo, abantu abahlukahlukene wenza PCB kuyodingeka Imiphumela ezahlukene, ngakho indlela yokwenza ? okuhle PCB ibhodi Ngenxa yokuhlangenwe nakho kwethu kwangaphambili, singathanda ukuxoxa imibono yethu izinto ezilandelayo:
1. Chaza imigomo yakho
Wathola umsebenzi design, kumelwe kuqala ukusula imigomo design, kuyinto Common PCB ibhodi , high-imvamisa PCB , ezincane signal processing PCB noma kukhona kokubili imvamisa high futhi signal processing encane PCB, uma kuyindodana PCB ezivamile , inqobo njengoba ukwenza isakhiwo ezinengqondo futhi icocekile, usayizi mechanical olunembile, Uma umugqa umthwalo futhi ujenga, izophathwa ngumuntu izindlela ezithile, lula umthwalo, ukuqinisa ujenga idrayivu, isihluthulelo ukuvimbela kuveza lo eside umugqa sika. lapho kunezinhlobo ezingaphezu kuka 40MHz isignali imigqa ebhodini, yezakhi ezikhethekile enzelwa lezi imigqa isignali, ezifana crosstalk.If imvamisa lingaphezulu, imikhawulo okwengeziwe ubude wiring, ngokuvumelana nemingcele ukusatshalaliswa senethiwekhi mbono, ukuxhumana phakathi high speed wesifunda futhi okunamathiselwe salo okunqumayo, uhlelo akunakugwenywa e design.With ngcono umnyango ngesivinini transmission, elayinini ngokumelene iyokwanda le crosstalk phakathi eduze isignali imigqa kuyoba ezilinganiselwe ekwandeni, ngokuvamile ngesivinini amandla ukusetshenziswa ukushabalalisa ukushisa kwe-circuit likhulu kakhulu, kufanele ubangele ukunakwa ngokwanele uma wenza ngesivinini PCB.
Lapho ibhodi kufanele millivolt ezingeni ngisho microvolt ezingeni lapho isignali enganamandla, isiginali uzodinga ukunakekelwa okukhethekile, isiginali encane ayinamandla, abasengozini khulu kwamanye eqinile isignali ukuphazamiseka, sivikele izindlela ngokuvamile kudingeka, kungenjalo kuzonciphisa kakhulu isignali ye-umsindo amasignali ratio.So ukuthi ewusizo aqwila out by umsindo futhi ayikwazi ngempumelelo likhishiwe.
Esikebheni kwakuneqembu esilinganisweni futhi kufanele kucatshangelwe ngesikhathi sesigaba design, indawo ebonakalayo ye test amaphuzu, ukuhlolwa iphuzu engayodwa izici akunakugwenywa, ngoba ezinye isignali amancane isignali imvamisa high ngqo wengeze Uphenyo ukukala.
Ngaphezu kwalokho, kunezinye izici ezihlobene, ezifana ungqimba amabhodi, ukuma iphakethe yezingxenye futhi amandla mechanical of the boards.Before okwenza PCB amabhodi, kufanele ube yini umgomo design engqondweni.
2. Qonda nezidingo umsebenzi yezingxenye esetshenziswa kusakhiwo
Njengoba sazi, kukhona ezinye izingxenye ekhethekile kusakhiwo baye izidingo ezikhethekile, ezifana Loti futhi APH esetshenziswa analog isignali amplifier, i-analog isignali amplifier ngoba amandla imfuneko ngoba bushelelezi, ezincane ripple.The sekulingisa encane izingxenye isignali kufanele igcinwe kude amandla kube devices.On ibhodi Oti, abancane isignali okhulisa ingxenye nayo eziklanyelwe nge buso ukuzivikela afune kuvikela nobe kusita ehlangeni kagesi interference.GLINK chips elisetshenziswa ibhodi NTOI yinqubo ECL, amandla ukusetshenziswa imfiva enkulu, inkinga ukushabalalisa ukushisa kumele iqhutshwe lapho isakhiwo kumele kube ukucabangela okukhethekile, uma indlu zemvelo, uyobeka GLINK chip komoya abushelelezi, futhi ngenxa yokushisa akuyona nethonya elikhulu kwabanye chips.If kukhona uphondo noma ezinye amandla high kudivayisi ebhodini, kungase futhi kubangele ukungcola ezibucayi amandla kufanele futhi unake ngokwanele.
3. Ukucutshungulwa isakhiwo ingxenye
Sakhiwo yezingxenye owokuqala okufanele sikucabangele ukusebenza esihlobene uxhumano izingxenye ndawonye ngangokunokwenzeka, ikakhulukazi abanye line high speed, nomhleli ukwenza kube kufushane ngokusemandleni ukuhlukanisa isignali amandla amancane i-signal device.In kwesisekelo lokuhlangana ukusebenza kwe-circuit, futhi kuyadingeka ukuba ucabangele ilungiselelo yezingxenye ukuze, enhle, ezikahle ukuze avivinye, ubukhulu mechanical ebhodini, isikhundla kwezisekelo, njll
Isikhathi ukudluliswa kunqanda isisekelo futhi interconnection ohlelweni ngesivinini futhi isici sokuqala kufanele ucatshangelwe lapho aklame system.Signal ku isikhathi ukudluliswa wayene nethonya elikhulu jikelele isivinini uhlelo, ikakhulukazi ngesivinini ECL izifunda, nakuba high speed okuhlangene wesifunda block ngokwayo, kodwa ngenxa phansi nge oluchazayo ezivamile (njalo cm 30 ubude, ngokuthi uyabambezeleka we 2 NS) ukuletha nesanda isikhathi ukubambezeleka, ungenza ijubane uhlelo ancipha kakhulu. Thanda irejista shift, esiphikisayo zokuvumelanisa le ukuvumelanisa izingxenye abasebenza kunye ikhadi, engcono ngenxa ezahlukene yokudlulisela ukubambezeleka nesikhathi isignali iwashi ebhodini ayilingani, kungaholela shift irejista umkhiqizo amaphutha, uma hhayi ipuleti, lapho ukuvumelanisa kuyisihluthulelo, kusukela emithonjeni iwashi zomphakathi exhunywe kwi-umugqa iwashi kufanele alingane ubude ebhodini.
4. Ukucutshungulwa wiring
Nge ukuklanywa OTNI futhi inkanyezi optical fibre inethiwekhi, ezingaphezu kuka 100MHz ijubane eliphezulu isignali umugqa kuyodingeka yakhelwe esikhathini esizayo. Ezinye nemiqondo eyisisekelo line high speed ziyokhokhwa lapha.
Transmission umugqa
Noma yimuphi "eside" indlela okuwuphawu on ephrintiwe wesifunda ibhodikungaba ibhekwe ukudluliswa line.If ukubambezeleka ukudluliswa emgqeni sifushane kunesikhathi isignali kuyanda, reflection yomnikazi ngesikhathi kuyanda isignali kuyoba submerged.No isavela overshoot, ukufinyela futhi ukushaya, ngoba ngaleso sikhathi, iningi Mos wesifunda, ngenxa yesikhathi ukuvelela umugqa ukudluliswa ukubambezeleka kwesikhathi likhulu kakhulu, ngakho-ke kungaba ngamamitha eside futhi kungekho distortion.And isignali okusheshayo logic izifunda, ikakhulukazi ultra-high speed ECL.
Endabeni izifunda ehlangene, ubude iminonjana kumele kakhulu mfushane ukuze silondoloze ubuqotho isignali ngenxa ngokushesha onqenqemeni ngesivinini.
Kunezindlela ezimbili ukwenza kukhona wesifunda ngesivinini esikhulu emsebenzini umugqa kuqhathaniswa eside ngaphandle ukuhlanekezela sina, isetshenziselwa ukwehla ngokushesha onqenqemeni TTL schottky diode clamping indlela, ukwenza ngiyibona kube kubanjwa diode ingaphansi kwe phansi ezingaba ingcindezi iconsi ezingeni ekunciphiseni ukufinyela ngemuva amplitude, kancane onqenqemeni ekuphumeni overshoot uvunyelwe, kodwa ezingeni "H" esimweni kuqhathaniswa okusezingeni eliphezulu okukhipha impedance kwe-circuit (50 ~ 80 Ω) attenuation .Ngaphezu kwalokho, ngenxa ezingeni "H" isimo amasosha omzimba, emikhulu inkinga ukufinyela akuyona oluvelele kakhulu, idivayisi ye-HCT chungechunge, uma usebenzisa i-schottky diode clamping kanye uchungechunge ukumelana ohlangothini ukuxhuma indlela, umphumela ngcono kuyoba sobala ngokwengeziwe.
Uma kukhona fan out agudle isignali, le TTL ekwakheni indlela echazwe ngenhla entula ayanda bit kanye onqenqemeni ngokushesha speed.Because khona ziyabonakala amagagasi emgqeni, bayoba bavame ukuba kuhlelwe ngesilinganiso okusezingeni eliphezulu, kanjalo okubangela ukuhlanekezela sina isignali kanye nokuncipha anti-ukuphazamiseka ability.Therefore, ukuze baxazulule le nkinga reflection, enye indlela ngokuvamile lisetshenziswa uhlelo ECL: umugqa impedance afanayo method.In ngale ndlela reflection silawulwa futhi ubuqotho isignali kuqinisekisiwe.