Mndandanda Wotsatira wa Ma PCB Opangidwa ndi Ma pafupipafupi

M'dziko lamakono la digito lothamanga kwambiri, ma PCB (ma circuit boards) omwe amasindikizidwa pafupipafupi kwambiri ndi maziko a ukadaulo wapamwamba monga kulumikizana kwa 5G, kuyenda kwa satellite, machitidwe a radar, makompyuta ogwira ntchito bwino, komanso zamagetsi apamwamba kwambiri. Ubwino wa kapangidwe ka PCB kothamanga kwambiri umakhudza mwachindunji kukhazikika, kugwira ntchito bwino, komanso kudalirika kwa makina onse amagetsi.

Kwa mainjiniya opanga mapangidwe a PCB, kudziwa bwino mfundo za kapangidwe ka RF PCB ndikupewa zolakwika zazikulu pakupanga ndikofunikira. Nkhaniyi ikuyang'ana kwambiri pa zoletsa zomwe zimachitika kawirikawiri pakupanga mapangidwe a PCB, ikufotokoza zomwe zimayambitsa komanso zotsatira zake, komanso ikuwonetsa kusiyana kwakukulu pakati pa mapangidwe apamwamba ndi otsika.

1, Zoletsa pa Kapangidwe ka Njira

✕ Kunyalanyaza Kufananiza kwa Impedance ya Khalidwe

Kutumiza kwa chizindikiro mu ma PCB apamwamba kumafuna kuwongolera kolimba kwa impedance, nthawi zambiri mkati mwa ± 5% ya zomwe zili mu target monga 50Ω kapena 75Ω. Kulephera kuganizira kukula kwa trace, malo, makulidwe a dielectric, ndi zinthu Dk kungayambitse kulephera kwa impedance, zomwe zimapangitsa kuti:

● Kuwunikira kwa chizindikiro
● Kupotoza mawonekedwe a mafunde
● Kuchuluka kwa zolakwika za bit
● Kuchepetsa kwambiri chizindikiro cha chizindikiro
Mwachitsanzo, m'malo osungira ma 5G, kusagwirizana kwa impedance kumabweretsa kutayika kwa mapaketi a data, kulumikizana kofooka, komanso kusadziwa bwino kwa ogwiritsa ntchito. Gwiritsani ntchito zida zoyeserera zamagetsi kuti muwerengere impedance molondola, ndipo nthawi zonse ganizirani za kulekerera kwa kupanga ndi kudalira kwa stackup.

✕ Topology Yosauka Yoyendetsera Njira

Kusankha njira zolakwika—monga njira zazitali kwambiri, zopapatiza, kapena zodzaza kwambiri—zingayambitse:

● Kuchedwa ndi kutayika kwa chizindikiro chifukwa cha kutalika kwambiri
● Kukana kwambiri komanso kutentha kwambiri kuchokera ku zinthu zopapatiza
● Kusokonezana pakati pa mizere yoyandikana
Tsatirani miyezo ya kapangidwe monga:
● YOTSATIRA ● FEXT Mu ma interfaces othamanga kwambiri (USB 3.0, HDMI), kufananiza ma tight differential pair (±5mil) ndi njira zabwino zoyendetsera ma routing ndizofunikira kwambiri kuti ma signal asunge bwino.

2, Zovuta Zokhudza Kupanga Kapangidwe ka Stackup

✕ Kuwerengera Zigawo ndi Kusankha Zinthu Mwachisawawa
Kuchuluka kwa zigawo kuyenera kuwonetsa kusinthasintha kwa ma circuit ndi zosowa zodzipatula. Zigawo zochulukirapo zimawonjezera kusinthasintha kwa mtengo ndi kukonza; zigawo zochepa kwambiri zimaletsa kukonzekera kwa chizindikiro ndi mphamvu.

Musamakondere kusankha zinthu: gwiritsani ntchito zinthu zomwe zimapezeka pafupipafupi monga Rogers RO4350B ndi:

● Chokhazikika cha dielectric chochepa (Dk)
● Chinthu chochepa chotulutsa madzi (Df)
Kugwiritsa ntchito FR4 yokhazikika kapena ma substrates osayenera mu mmWave PCBs (24–52GHz) kumabweretsa:

● Kutayika kwakukulu kwa chizindikiro
● Kusakhazikika kwa Impedance
● Kuchepetsa mphamvu yotumizira deta

✕ Kunyalanyaza Zofunikira Zolembetsa ndi Kuyika Lamination Pakati pa Zigawo

Kusalingana kwa ma interlayer > ± 50μm kungayambitse ma shorts, ma open circuits, ndi kulephera kugwira ntchito bwino. Kusakhazikika bwino kwa lamination kumabweretsa:

● Kuchotsa ming'alu
● Kuwunikira kwa chizindikiro
● Kusakhazikika kwa makina
Opanga ayenera kugwirizana kwambiri ndi opanga, ponena kuti:
● Kutentha kwa lamination: 180–220°C
● Kupanikizika: 5–10MPa
● Nthawi: Mphindi 30–60
● Kulinganiza kwa mkuwa ndi mikwingwirima yofanana kuti muchepetse kupsinjika

3, Kudzera ndi Pad Design Taboos

✕ Kudzera mu Mtundu ndi Kukula Kolakwika kwa Zizindikiro Zothamanga Kwambiri

Kusankha mabowo otulukira m'malo mwa ma vias osawoneka kapena obisika kumawonjezera mphamvu ya parasitic inductance/capacitance, zomwe zimayambitsa:

● Kuchedwa kwa chizindikiro
● Kupotoza
● Kuwunikira m'njira zothamanga kwambiri
Komanso, pewani kukhala ndi ma diameter ang'onoang'ono kwambiri (● Kusakhazikika bwino kwa chibowo
● Kupanda pulasitala bwino
● Kukana kwambiri
Kusankha bwino kudzera mu njira yolondola kumawonjezera umphumphu wa chizindikiro ndi kupanga bwino.

✕ Kunyalanyaza Kapangidwe ka Pad ndi Kugwirizana kwa Soldering

Mapepala ayenera kupangidwa kuti agwirizane ndi njira yosokera yomwe ikufunidwa:
● Kuthira madzi m'madzi kumafuna kukula koyenera kwa ma pedi kuti munyowetse
● Kusoka mafunde kumafuna malo otalikirana kuti asatseke mawaya
Zomaliza pamwamba monga ENIG (Electroless Nickel Immersion Gold) zimapangitsa kuti solder isasokonekere bwino komanso kuti isawotchedwe. Kapangidwe koyipa kapena zomaliza zake zikhale zoyipa:
● Malo ozizira
● Kulumikiza kwa solder
● Kutulutsa okosijeni ndi ma circuits otseguka

4, Zolakwika, Zomwe Zimayambitsa, ndi Mipata Yabwino Yopangidwira

Zizindikiro Zofala za Chilema

● Kuchepetsa chizindikiro ndi kusokoneza mawonekedwe a mafunde

● Kulankhulana pakati pa zizindikiro

● Kugawanika kwa zigawo ndi ma circuits afupiafupi

● Kusweka kwa ma trace fractures, kudzera mu kutsekeka, kapena kusungunuka kwa ma pad

Zomwe Zimayambitsa

● Kusagwirizana kwa impedance chifukwa cha kuwerengera kolakwika kwa ma track

● Kusankha zinthu zosakwanira pa ma RF frequency

● Kukonzekera kolakwika kwa ma stackup popanda kulinganiza njira

● Kusaganiziridwa bwino chifukwa cha mankhwala ophera tizilombo komanso kulekerera kuboola

● Miyeso ya Pad sikugwirizana ndi njira yosokera

Kuyerekeza Kusiyana kwa Kapangidwe

5, Chimwemwe Chochuluka Chingathe Kuthana ndi Mavuto Onse

Cholakwika chilichonse cha kapangidwe—kuyambira kusagwirizana kwa impedance ndi kusagwirizana kwa ma crosstalk mpaka kulephera kwa stackup komanso kusagwira bwino ntchito kwa kapangidwe—chingasokoneze magwiridwe antchito a RF PCB. Ku Rich Full Joy, mainjiniya athu a RF ndi akatswiri opanga zinthu amagwira ntchito limodzi kuti:

● Onetsetsani kuti mapulani opangira (DFM) akutsatira malamulo
● Gwiritsani ntchito zida zamakono zoyeserera za EM
● Gwiritsani ntchito luso lapamwamba la zinthu
● Perekani mapangidwe abwino komanso okonzeka kupanga zinthu
Kaya ndi malo oyambira a 5G, makina a radar, kapena kulumikizana kwa satellite, timaonetsetsa kuti PCB yanu yothamanga kwambiri imagwira ntchito mwachangu, mwachilungamo, komanso modalirika.

6、Gwirizanani ndi Chimwemwe Chochuluka: Kupanga Mwanzeru, Kuchita Bwino

Ndi zaka zambiri zaukadaulo wa RF PCB, Rich Full Joy waphunzira bwino sayansi yowongolera ma signal pafupipafupi. Timaphatikiza kapangidwe koyendetsedwa ndi simulation, sayansi ya zida, ndi kupanga kwapamwamba kuti tipange ma PCB omwe amapambana miyezo yolimba kwambiri komanso magwiridwe antchito.

Titsateni kuti mudziwe zambiri za akatswiri, kapena titumizireni uthenga kuti tikambirane za pulojekiti yanu yotsatira yomwe imachitika pafupipafupi!