Lapho wenza i-PCB umzila, ngenxa yomsebenzi wokuhlaziya wokuqala awenziwanga noma awenziwanga, ukucubungula ngemuva kokucubungula kunzima. Uma ibhodi le-PCB liqhathaniswa nedolobha lethu, izingxenye zifana nomugqa phezu komugqa wazo zonke izinhlobo zezakhiwo, imigqa yesignali iyimigwaqo nemigwaqo edolobheni, i-flyover roundabout island, ukuvela komgwaqo ngamunye ukuhlela kwayo okuningiliziwe, izintambo nazo okufanayo.
1. Izidingo ezibalulekile zezintambo
A) Kukhethwa imigqa yesignali engukhiye: ukunikezwa kwamandla, isignali encane ye-analog, isignali yesivinini esikhulu, isignali yewashi, isignali yokuvumelanisa nezinye izimpawu ezibalulekile.
B) Isimiso sokubaluleka kokuminyana kwezintambo: Qala ukufaka izintambo kusuka engxenyeni enobudlelwano bokuxhumana obuyinkimbinkimbi kakhulu ebhodini. Ikhebula iqala endaweni exhumene kakhulu ebhodini.
C) Izexwayiso zokucubungula isignali engukhiye: zama ukunikeza isendlalelo sezintambo esikhethekile samasignali abalulekile njengesignali yewashi, isignali yefrikhwensi ephezulu nesignali ebucayi, futhi uqinisekise indawo encane yeluphu. Uma kunesidingo, ukuvikela nokwandisa isikhala sokuphepha kufanele kwamukelwe. Qinisekisa ikhwalithi yesiginali.
D) Inethiwekhi enezidingo zokulawula i-impedance izohlelwa kusendlalelo sokulawula i-impedance, futhi ukuhlukaniswa kwayo kwesignali kuzogwenywa.
2.Ukulawula i-wiring scrambler
A) Ukuhunyushwa komgomo we-3W
Ibanga phakathi kwemigqa kufanele libe izikhathi ezi-3 ububanzi bomugqa. Ukuze kuncishiswe i-crosstalk phakathi kwemigqa, isikhala somugqa kufanele sibe sikhulu ngokwanele. Uma ibanga lesikhungo somugqa lingekho ngaphansi kwezikhathi ezi-3 ububanzi bomugqa, i-70% yenkambu kagesi phakathi kwemigqa ingagcinwa ngaphandle kokuphazanyiswa, okubizwa ngokuthi umthetho we-3W.
B) Ukulawula ukuphazamisa: I-CrossTalk ibhekisela ekuphazamiseni phakathi kwamanethiwekhi ahlukene ku-PCB okubangelwa izintambo ezinde ezihambisanayo, ikakhulukazi ngenxa yesenzo sokusabalaliswa kwamandla kanye nokusatshalaliswa kwe-inductance phakathi kwemigqa ehambisanayo. Izinyathelo eziyinhloko zokunqoba i-crosstalk yilezi:
I. Khulisa isikhala sekhebula ehambisanayo futhi ulandele umthetho we-3W;
Ii. Faka izintambo zokuhlukanisa umhlabathi phakathi kwezintambo ezihambisanayo
Iii. Yehlisa ibanga phakathi kwesendlalelo sekhebula nendiza yaphansi.
3. Imithetho ejwayelekile yezidingo zezintambo
A) Indlela yendiza eseduze i-orthogonal. Gwema imigqa yesignali ehlukene kungqimba oluseduze ukuze unciphise ukuphazamiseka okungadingekile kwe-inter-layer; Uma lesi simo sinzima ukusigwema ngenxa yemikhawulo yesakhiwo sebhodi (njengamanye ama-backplanes), ikakhulukazi uma izinga lesignali liphezulu, kufanele ucabange ukuhlukanisa izingqimba zezintambo endizeni yaphansi kanye nezintambo zesignali phansi.
B) Izintambo zamadivayisi amancane ahlukene kufanele zilingane, futhi i-SMT pad eholayo enezikhala ezisondelene kakhulu kufanele ixhunywe ngaphandle kwephedi. Ukuxhumana okuqondile phakathi kwephedi akuvunyelwe.
C) Umthetho omncane we-loop, okungukuthi, indawo yeluphu eyakhiwe umugqa wesignali kanye neluphu yayo kufanele ibe mncane ngangokunokwenzeka. Indawo encane ye-loop, iyancipha imisebe yangaphandle kanye nokuncane ukuphazamiseka kwangaphandle.
D) Izintambo ze-STUB azivunyelwe
E) Ububanzi bezintambo zenethiwekhi efanayo kufanele bugcinwe bufana. Ukuhluka kobubanzi bezintambo kuzobangela ukungalingani kwesici somugqa. Uma isivinini sokudlulisela siphezulu, ukubonakaliswa kuzokwenzeka. Ngaphansi kwezinye izimo, ezifana isixhumi lead wire, BGA iphakheji lead wire isakhiwo esifanayo, ngenxa yesikhala encane ingase ingakwazi ukugwema ukushintsha kobubanzi bomugqa, kufanele sizame ukunciphisa ubude obusebenzayo bengxenye ephakathi engaguquki.
F) Vimbela izintambo zesignali ukuthi zingakhi izihibe ezizimele phakathi kwezendlalelo ezihlukene. Lolu hlobo lwenkinga kulula ukwenzeka ekwakhiweni kwamapuleti amaningi, futhi i-self-loop izodala ukuphazamiseka kwemisebe.
G) I-engeli ebukhali kanye ne-engeli engakwesokudla kufanele igwenywePCB design, okuholela emisebeni engadingekile, kanye nokusebenza kwenqubo yokukhiqizaPCBakukuhle.
