Ukukhethwa kwebhodi le-PCB kufanele kufinyelele ibhalansi phakathi kwezidingo zedizayini yokuhlangabezana nokukhiqizwa ngobuningi nezindleko. Izidingo zokuklama zihlanganisa izingxenye zikagesi nezemishini. Le nkinga yezinto ezibonakalayo ngokuvamile ibaluleke kakhulu lapho uklama amabhodi e-PCB anesivinini esikhulu (imvamisa enkulu kune-GHz).
Isibonelo, izinto ezisetshenziswa kakhulu ze-FR-4 manje sezinokulahleka kwe-dielectric ngemvamisa yama-GHz ambalwa, okunomthelela omkhulu ekuncipheni kwesignali, futhi okungenzeka kungafaneleki. Mayelana nogesi, qaphela ukuthi ukulahleka kwe-dielectric kanye ne-dielectric kuyafaneleka yini imvamisa eklanyelwe.2. Ungakugwema kanjani ukuphazamiseka kwefrikhwensi ephezulu?
Umqondo oyisisekelo wokugwema ukuphazamiseka kwemvamisa ephezulu ukunciphisa ukugxambukela kwenkundla kagesi yamasignali amaza aphezulu, okuyilokho okubizwa nge-crosstalk (Crosstalk). Ungakwazi ukwandisa ibanga phakathi kwesiginali yesivinini esikhulu kanye nesiginali ye-analog, noma wengeze imikhondo yokuqapha/i-shunt eduze kwesiginali ye-analog. Naka futhi ukuphazamiseka komsindo kusuka endaweni yedijithali kuya endaweni ye-analog.3. Indlela yokuxazulula inkinga yobuqotho besignali kumklamo wesivinini esikhulu?
Ubuqotho besignali ngokuyisisekelo buyinkinga yokufanisa i-impedance. Izinto ezithinta ukufaniswa kwe-impedance zifaka ukwakheka nokukhinyabezeka kokuphumayo komthombo wesignali, isici esivimbelayo sokulandela umkhondo, izici zesiphetho somthwalo, kanye ne-topology yokulandela umkhondo. Isixazululo siwukuthembela ku-topology yokunqanyulwa nokulungiswa kwezintambo.
4. Indlela yokuhlukanisa izintambo ibonakala kanjani?
Kunamaphuzu amabili okufanele uwanake ekuhlelweni kwepheya ehlukile. Enye iwukuthi ubude bezintambo ezimbili kufanele bube bude ngangokunokwenzeka, kanti enye iwukuthi ibanga phakathi kwezintambo ezimbili (leli banga linqunywa yi-impedance ehlukile) kufanele igcinwe njalo, okungukuthi, ukugcina ifana. Kunezindlela ezimbili ezifanayo, eyodwa ukuthi imigqa emibili igijima ohlangothini olulodwa, kanti enye iwukuthi imigqa emibili igijima ezingqimbeni ezimbili eziseduze (ngaphezulu-ngaphansi). Ngokuvamile, uhlangothi lwangaphambili lwe-side-by-side (i-side-by-side, side-by-side) lusetshenziswa ngezindlela eziningi.
5. Ungazibona kanjani izintambo ezihlukene zolayini wesiginali yewashi onetheminali eyodwa kuphela yokuphumayo?
Ukusebenzisa izintambo ezihlukanisayo, kunengqondo ukuthi umthombo wesignali nomamukeli nakho kuyizimpawu ezihlukanisayo. Ngakho-ke, akunakwenzeka ukusebenzisa izintambo ezihlukanisayo zesignali yewashi enetheminali eyodwa kuphela yokuphumayo.
6. Ingabe i-resistor ehambisanayo ingezwa phakathi kwamapheya emigqa ehlukene ekugcineni kokwamukela?
Ukumelana okufanayo phakathi kwamapheya emigqa ehlukile ekugcineni kokwamukela kuvame ukungezwa, futhi inani layo kufanele lilingane nenani le-impedance ehlukile. Ngale ndlela ikhwalithi yesiginali izoba ngcono.
7. Kungani izintambo zamapheya ahlukene kufanele zisondele futhi zihambisane?
Izintambo zamapheya ahlukene kufanele zivaleke ngokufanele futhi zihambisane. Okubizwa ngokuthi ukusondelana okufanele kungenxa yokuthi ibanga lizothinta inani le-impedance ehlukile, okuyipharamitha ebalulekile yokuklama amapheya ahlukene. Isidingo se-parallelism futhi siwukugcina ukuvumelana kwe-impedance ehlukile. Uma imigqa emibili ikude ngokuzumayo futhi iseduze, i-impedance ehlukile izobe ingahambisani, okuzothinta ubuqotho besignali nokubambezeleka kwesikhathi.