Ukubaluleka kobubanzi bomugqa we-PCB ekwakhiweni kwe-PCB

Buyini ububanzi bomugqa?

Ake siqale ngezisekelo. Buyini ngempela ububanzi bokulandela? Kungani kubalulekile ukucacisa ububanzi bethrekhi ethile? Inhloso ye PCB ukuhlanganisa izintambo ukuxhuma noma yiluphi uhlobo lwesiginali kagesi (i-analog, idijithali noma amandla) kusuka kunodi eyodwa kuya kwenye.

I-node ingaba yiphini yengxenye, igatsha lokulandela umkhondo noma indiza enkulu, noma iphedi elingenalutho noma iphuzu lokuhlola lokuphenya. Ububanzi bokulandela umkhondo kuvame ukukalwa ngama-mils noma izinkulungwane zamasentimitha. Ububanzi bezintambo ezijwayelekile zamasiginali ajwayelekile (azikho izidingo ezikhethekile) kungaba ngamasentimitha amaningana ubude ebangeni lama-7-12 mils, kepha izinto eziningi kufanele zicatshangelwe lapho kuchazwa ububanzi bezintambo nobude.

ipcb

Uhlelo lokusebenza luvamise ukushayela ububanzi bezintambo nohlobo lwentambo ekwakhiweni kwe-PCB futhi, kwesinye isikhathi, kuvamise ukulinganisa izindleko zokukhiqiza ze-PCB, ukuminyana / usayizi webhodi, nokusebenza. Uma ibhodi linezidingo ezithile zokuklama, njengokusebenza kwejubane, umsindo noma ukucindezela ukuhlangana, noma amandla wamanje / i-voltage ephezulu, ububanzi nohlobo lokulandela umkhondo kungabaluleke ngaphezu kokuqhakambisa izindleko zokukhiqiza ze-PCB engenalutho noma usayizi webhodi jikelele.

Incazelo ephathelene nezintambo ekukhiqizeni i-PCB

Typically, the following specifications related to wiring begin to increase the cost of manufacturing bare PCB.

Imiklamo eminyene kakhulu ehlanganisa ukuthatha isikhala kwe-PCB, okufana ne-BGA ehlukaniswe kahle kakhulu noma amabhasi wokubala wesiginali ephezulu, kungadinga ububanzi bomugqa we-2.5 mil, kanye nezinhlobo ezikhethekile zemigodi enqamula ngobubanzi obufinyelela ku-6 mil, njengoba laser kubhola microthrough-izimbobo. Ngakolunye uhlangothi, eminye imiklamo yamandla aphezulu ingadinga izintambo ezinkulu kakhulu noma izindiza, kudle izingqimba zonke futhi kuthelwe ama-ounces ashubile kunokujwayelekile. Kuzicelo ezinomkhawulo wesikhala, kungadingeka amapuleti amancane kakhulu aqukethe izingqimba eziningana kanye nobukhulu obulinganiselwe bokuphonsa ithusi lobukhulu besigamu (0.7 mil ukujiya).

Kwezinye izimo, ukwakheka kokuxhumana kwejubane kusuka kolunye uhlangothi kuya kolunye kungadinga ukuxhunywa nge-impedance elawulwayo nobubanzi obuthile kanye nesikhala phakathi komunye nomunye ukunciphisa ukubumbana nokuhlangana kokungeniswa. Noma ukwakhiwa kungadinga ubude obuthile ukufanisa amanye amasiginali afanele ebhasini. Izicelo ezinamandla amakhulu zidinga izici ezithile zokuphepha, njengokunciphisa ibanga phakathi kwezimpawu ezimbili eziveziwe zokuhlukanisa ukuvimbela ukuhlangana. Akunandaba nezimpawu noma izici, ukulandelela izincazelo kubalulekile, ngakho-ke ake sihlole izinhlelo zokusebenza ezahlukahlukene.

Ububanzi obuhlukahlukene bezintambo nobukhulu

PCBS typically contain a variety of line widths, as they depend on signal requirements. Imikhondo emihle ekhonjisiwe yenzelwe amasiginali wezinga elijwayelekile le-TTL (transistor-transistor logic) futhi ayinazidingo ezikhethekile zokuvikelwa okuphezulu kwamanje noma komsindo.

Lezi kuzoba izinhlobo ezivame kakhulu zezintambo ebhodini.

Izintambo ezijiyile zenzelwe amandla okuphatha amanje futhi zingasetshenziselwa iziphambeko noma imisebenzi ehlobene namandla edinga amandla aphakeme, njengabalandeli, izinjini, nokudluliswa kwamandla okujwayelekile kuzingxenye ezisezingeni eliphansi. Ingxenye engaphezulu kwesobunxele yalesi sibalo ikhombisa nesiginali yokuhlukanisa (i-USB esheshayo) echaza isikhala nobubanzi obuthile ukuhlangabezana nezidingo ze-impedance ka-90 ω. Umdwebo 2 ukhombisa ibhodi lesifunda elijiyene kancane elinezendlalelo eziyisithupha futhi elidinga umhlangano we-BGA (ball grid array) odinga izintambo ezinhle.

Ungabala kanjani ububanzi bomugqa we-PCB?

Ake sidabule inqubo yokubala ububanzi bokulandela obuthile besiginali yamandla edlulisa okwamanje kusuka entweni yamandla iye kudivayisi eyakhelekayo. Kulesi sibonelo, sizobala ububanzi bolayini obuncane bendlela yamandla emoto ye-DC. Indlela yamandla iqala ku-fuse, iwele i-H-bridge (ingxenye esetshenziselwa ukuphatha ukudluliswa kwamandla kuwo wonke ama-motor motor e-DC), futhi inqamulelwa kusixhumi semoto. Isilinganiso samanje samanje esiqhubekayo esidingekayo semoto ye-DC cishe ngama-ampere ama-2.

Manje, izintambo ze-PCB zisebenza njenge-resistor, futhi uma isikhathi eside futhi sincipha i-wiring, ukumelana okuthe xaxa kuyangezwa. Uma i-wiring ingachazwanga kahle, i-current high ingalimaza i-wiring kanye / noma ibangele ukwehla okukhulu kwe-voltage emotweni (okuholele ekwehliseni isivinini). Uma sicabanga ngezimo ezithile ezijwayelekile, njengokuthululwa okukodwa kokuthusi nokushisa kwegumbi ngesikhathi sokusebenza okujwayelekile, sidinga ukubala ububanzi bomugqa omncane nokwehla kwengcindezi okulindelekile kulobo bubanzi.

Isikhala sekhebula le-PCB nobude

Okwakhiwa kwedijithali okunokuxhumana kwejubane eliphezulu, isikhala esithile nobude obuguquliwe kungadingeka ukunciphisa i-crosstalk, coupling, kanye ne-reflection. Ngale njongo, ezinye izinhlelo zokusebenza ezijwayelekile ziyizimpawu ezahlukanisiwe ezenzelwe i-USB namasiginali wokuhlukaniswa asuselwa ku-RAM. Imvamisa, i-USB 2.0 izodinga umzila wokwehluka ku-480Mbit / s (iklasi lejubane le-USB) noma ngaphezulu. Lokhu kungenxa yokuthi i-USB enejubane elikhulu isebenza ngokuvama nokwehluka okuphansi kakhulu, okusondeza ileveli yesiginali jikelele ngomsindo wangemuva.

Kunezinto ezintathu ezibalulekile okufanele uzicabangele lapho uhambisa izintambo ze-USB ezisheshayo: ububanzi bocingo, isikhala sokuhola, nobude bekhebula.

Konke lokhu kubalulekile, kepha okubaluleke kakhulu kokuthathu ukuqinisekisa ukuthi ubude bemigqa emibili buhambisana kakhulu. As a general rule of thumb, if the lengths of the cables differ from each other by no more than 50 mils, this significantly increases the risk of reflection, which may result in poor communication. I-90 ohm impedance efanayo iyincazelo ejwayelekile yokuhlukanisa izintambo zombili. Ukufeza le nhloso, umzila kufanele ulungiselelwe ngobubanzi nangesikhala.

Umdwebo 5 ukhombisa isibonelo sokubhangqa okwehlukile kwezintambo ezihamba ngesivinini ezingena nge-USB eziqukethe izintambo ezi-12 mil ububanzi ngezikhathi ezingama-15 mil.

Interfaces for memory-based components that contain parallel interfaces will be more constrained in terms of wire length. Isoftware esezingeni eliphezulu kakhulu ye-PCB izoba namandla okulungiswa kobude enza ngcono ubude bomugqa ukufanisa wonke amasiginali afanele ebhasini elihambisanayo. Umdwebo 6 ukhombisa isibonelo sesakhiwo se-DDR3 ngentambo yokulungisa ubude.

Iminonjana nezindiza zokugcwaliswa komhlaba

Ezinye izinhlelo ezinezinto ezizwakala umsindo, njengama-chips angenantambo noma ama-antenna, zingadinga ukuvikelwa okwengeziwe. Ukuklama izintambo nezindiza ezinezimbobo zomhlaba ezishumekiwe kungasiza kakhulu ekunciphiseni ukuhlangana kwezintambo eziseduze noma ukukha izindiza nezimpawu ezingekho ebhodini ezingena emaphethelweni ebhodi.

Figure 7 shows an example of a Bluetooth module placed near the edge of the plate, with its antenna outside a thick line containing embedded through-holes connected to the ground formation. Lokhu kusiza ukuhlukanisa i-antenna kwamanye amasekethe ezindiza nezindiza.

This alternative method of routing through the ground can be used to protect the board circuit from external off-board wireless signals. Umdwebo 8 ukhombisa i-PCB ezwakala umsindo enendiza efakwe ngaphakathi emgodini eceleni komngcele webhodi.

Izindlela ezihamba phambili zokwenza izintambo ze-PCB

Izici eziningi zinquma izici zentambo zensimu ye-PCB, ngakho-ke qiniseka ukuthi ulandela imikhuba emihle lapho uxhuma i-PCB yakho elandelayo, futhi uzothola ibhalansi phakathi kwezindleko ze-PCB fab, ukuminyana kwesekethe, kanye nokusebenza kukonke.