Kodi m’lifupi mwake ndi chiyani?

Tiyeni tiyambe ndi zoyambira. Kodi m’lifupi mwake ndikutani kwenikweni? Chifukwa chiyani kuli kofunikira kutchula mtundu wakutambasula? Cholinga cha PCB Kulumikizana ndikulumikiza mtundu wina uliwonse wamagetsi (analogi, digito kapena mphamvu) kuchokera pamfundo ina kupita kwina.

Node ikhoza kukhala pini yophatikizira, nthambi yantchito yayikulu kapena ndege, kapena pedi yopanda kanthu kapena poyeserera pofufuza. Zowonjezera zazitali nthawi zambiri zimayezedwa ma mils kapena mainchesi masauzande. Kukula kwazolumikizira koyenera kwa zizolowezi wamba (palibe zofunikira zapadera) kumatha kukhala mainchesi angapo m’litali mwa 7-12 mils, koma zinthu zambiri ziyenera kuganiziridwa pofotokoza kukula ndi kutalika kwa zingwe.

Kugwiritsa ntchito kumayendetsa mulifupi ndi zingwe zamagetsi mu kapangidwe ka PCB ndipo, nthawi ina, nthawi zambiri zimayesa mtengo wopangira PCB, kuchuluka kwa bolodi / kukula, ndi magwiridwe antchito. Ngati bolodi ili ndi zofunikira pakapangidwe kake, monga kukhathamiritsa kwa liwiro, phokoso kapena kuponderezana, kapena kuthamanga kwaposachedwa / magetsi, m’lifupi mwake ndi mtundu wazomwe zitha kukhala zofunikira kwambiri kuposa kukhathamiritsa mtengo wopanga wa PCB wopanda kanthu kapena kukula kwa bolodi.

Mfundo zokhudzana ndi Kulumikizana mu kupanga PCB

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

Mapangidwe apamwamba kwambiri omwe amaphatikiza kutenga malo kwa PCB, monga ma BGA osakanikirana bwino kapena mabasi apamwamba owerengera ofanana, angafunike mzere wa 2.5 mil, komanso mitundu yapadera yolowera m’mabowo okhala ndi diameters mpaka 6 mil, monga laser lokumba mabowo obowerera. Mofananamo, mapangidwe amphamvu zamagetsi atha kufuna zingwe zazikulu kapena ndege zazikulu, kumangodya zigawo zonse ndikutsanulira ma ounsi omwe ndi olimba kuposa muyezo. Pogwiritsa ntchito malo ochepa, mbale zochepa kwambiri zomwe zimakhala ndi zigawo zingapo komanso mkuwa wochepa wamkuwa (0.7 mil makulidwe) angafunike.

Nthawi zina, mapangidwe olumikizirana mwachangu kuchokera kuzipangizo zina amafunika kulumikizana ndi maimidwe oyendetsedwa bwino komanso kutalika kwake ndikutalikirana pakati pawo kuti muchepetse kulumikizana komanso kulumikizana. Kapenanso kapangidwe kameneka kangafune kutalika kwakeko kuti kifanane ndi zikwangwani zina m’basi. Ntchito zamagetsi zamagetsi zimafunikira zinthu zina zachitetezo, monga kuchepetsa mtunda pakati pazizindikiro ziwiri zowonekera popewa kuyimitsidwa. Osatengera mawonekedwe kapena mawonekedwe, kutsatira matanthauzidwe ndikofunikira, chifukwa chake tiyeni tiwunikenso ntchito zosiyanasiyana.

Ma waya osiyanasiyana ndi makulidwe osiyanasiyana

PCBS typically contain a variety of line widths, as they depend on signal requirements. Zotsatira zabwino kwambiri zomwe zawonetsedwa ndizazizindikiro za TTL (transistor-transistor logic) zam’mizere ndipo zilibe zofunikira zapadera pakatetezedwe katsopano kapena phokoso.

Izi zidzakhala mitundu yolumikizidwa kwambiri ya bolodi.

Kulumikizana kocheperako kwapangidwa kuti kukhale kosakwanira pakadali pano ndipo itha kugwiritsidwa ntchito ngati zotumphukira kapena ntchito zokhudzana ndi mphamvu zomwe zimafunikira mphamvu yayikulu, monga mafani, ma mota, ndikusinthira kwamphamvu kumagawo azigawo zochepa. Gawo lakumanzere lakumanzere limawonetsanso chizindikiro chosiyanitsa (USB yothamanga kwambiri) chomwe chimafotokoza malo ndi mulifupi kuti zikwaniritse zosowa za 90 ω. Chithunzi 2 chikuwonetsa bolodi loyenda pang’ono lokhala ndi zigawo zisanu ndi chimodzi ndipo limafunikira msonkhano wa BGA (mpira grid) womwe umafunikira kulumikizana bwino.

Kodi kuwerengera PCB mzere m’lifupi?

Tiyeni tidutse pakuwunika kwakanthawi kochepa kwa chizindikiritso champhamvu chomwe chimasunthira pakadali pano kuchokera pachinthu chamagetsi kupita pachipangizo chammbali. Mu chitsanzo ichi, tiwerengera mulingo wocheperako wa njira yamagalimoto a DC. Njira yamagetsi imayambira pa fuseti, imadutsa H-mlatho (chinthu chomwe chimagwiritsidwa ntchito kuyang’anira kufalikira kwamagetsi kudutsa DC motor windings), ndipo chimathera pa cholumikizira mota. Makulidwe apakatikati opitilira omwe amafunikira ndi DC mota ndi pafupifupi 2 amperes.

Tsopano, zingwe za PCB zimakhala zotsutsana, ndipo zazitali komanso zochepetsera zingwe, kulimbana kumawonjezeredwa. Ngati zingwe sizinafotokozeredwe molondola, kuthamanga kwaposachedwa kumatha kuwononga zingwe ndi / kapena kuyambitsa kutsika kwamagetsi kwamagalimoto (kumachepetsa liwiro). Ngati tingaganizire zina ndi zina, monga kuthira mkuwa kamodzi ndi kutentha kwa firiji nthawi zonse, tiyenera kuwerengera mulingo wocheperako komanso kupsinjika koyembekezereka kutsika m’lifupi.

Chingwe cha PCB ndi kutalika

Pazipangidwe zadijito zokhala ndi mauthenga othamanga kwambiri, malo enaake ndi kutalika kosinthika kungafunike kuti muchepetse chopingasa, kulumikizana, ndikuwonetsa. Pachifukwa ichi, ntchito zina zodziwika bwino ndizosiyanitsa kochokera pa USB ndi zizindikiritso zofananira za RAM. Nthawi zambiri, USB 2.0 imafunikira masanjidwe oyenda pa 480Mbit / s (USB yothamanga kwambiri) kapena kupitilira apo. Izi ndichifukwa choti USB yothamanga kwambiri imagwira ntchito pama voltages otsika ndi kusiyanasiyana, kubweretsa mulingo wazizindikiro pafupi ndi phokoso lakumbuyo.

Pali zinthu zitatu zofunika kuziganizira mukamayendetsa zingwe zothamanga kwambiri za USB: kutalika kwa waya, malo otsogola, ndi kutalika kwa chingwe.

Zonsezi ndizofunikira, koma chofunikira kwambiri pa atatuwa ndikuwonetsetsa kuti kutalika kwa mizere iwiri ikufanana momwe zingathere. 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. 90 ohm ofananira ndi impedance ndikutanthauzira kwakukulu kwa ma waya awiri osiyana. Kuti mukwaniritse cholingachi, kuyendetsa bwino kuyenera kukhathamiritsidwa m’lifupi ndikutalikirana.

Chithunzi 5 chikuwonetsa chitsanzo cha mitundu iwiri yopanga ma waya othamanga kwambiri a USB omwe amakhala ndi zingwe za 12 mil mulifupi mu 15 mil.

Interfaces for memory-based components that contain parallel interfaces will be more constrained in terms of wire length. Mapulogalamu ambiri apamwamba a PCB amakhala ndi kusintha kwakutali komwe kumakulitsa kutalika kwa mzere kuti agwirizane ndi zizindikilo zonse m’basi lofananira. Chithunzi 6 chikuwonetsa chitsanzo cha mawonekedwe a DDR3 okhala ndi zingwe zosinthira kutalika.

Zotsatira ndi ndege zodzazidwa pansi

Mapulogalamu ena okhala ndi zinthu zosamveka phokoso, monga tchipisi tating’onoting’ono kapena tinyanga, angafunikire kutetezedwa pang’ono. Kupanga zingwe ndi ndege zokhala ndi mabowo ophatikizidwa zingathandize kwambiri kuchepetsa kulumikizana kwa zingwe zapafupi kapena kunyamula ndege ndi zikwangwani zomwe zimakwera m’mbali mwa bolodi.

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. Izi zimathandizira kupatula ma antenna kuchokera kuma circuits ena ndi ndege.

This alternative method of routing through the ground can be used to protect the board circuit from external off-board wireless signals. Chithunzi 8 chikuwonetsa PCB yomvera phokoso yokhala ndi ndege yolowedwa mozungulira yomwe ili pafupi ndi bolodi.

Njira zabwino kwambiri zolumikizira PCB

Zambiri zimafotokozera mawonekedwe a gawo la PCB, chifukwa chake onetsetsani kuti mukutsata njira zabwino mukamalumikiza PCB yanu yotsatira, ndipo mupeza malire pakati pa mtengo wa PCB, kachulukidwe ka dera, ndi magwiridwe antchito onse.