Kodi zigawo za AGND ndi DGND ziyenera kulekanitsidwa?
Yankho losavuta ndiloti zimatengera momwe zinthu zilili, ndipo yankho latsatanetsatane ndiloti nthawi zambiri sali olekanitsidwa.Chifukwa nthawi zambiri, kulekanitsa wosanjikiza pansi kumangowonjezera inductance ya kubwerera panopa, zomwe zimabweretsa zoipa zambiri kuposa zabwino.Fomu V = L (di/dt) imasonyeza kuti pamene inductance ikuwonjezeka, phokoso lamagetsi likuwonjezeka.Ndipo pamene kusintha kwamakono kukuwonjezeka (chifukwa chiwerengero cha chitsanzo chosinthira chikuwonjezeka), phokoso lamagetsi lidzawonjezekanso.Choncho, zigawo zoyambira ziyenera kugwirizana pamodzi.
Chitsanzo ndi chakuti m'mapulogalamu ena, kuti agwirizane ndi zofunikira zamapangidwe achikhalidwe, mphamvu za basi zonyansa kapena zozungulira digito ziyenera kuyikidwa m'madera ena, komanso ndi zopinga za kukula, kupanga bolodi silingakwanitse kugawa bwino, mu izi. nkhani, osiyana maziko wosanjikiza ndi chinsinsi kukwaniritsa ntchito yabwino.Komabe, kuti mapangidwe onse akhale ogwira mtima, zigawo zoyambirazi ziyenera kulumikizidwa palimodzi penapake pa bolodi ndi mlatho kapena malo olumikizirana.Choncho, malo olumikizirana ayenera kugawidwa mofanana pamagulu olekanitsidwa oyambira.Pamapeto pake, nthawi zambiri pamakhala malo olumikizirana pa PCB omwe amakhala malo abwino kwambiri obwererako kuti adutse popanda kuwononga magwiridwe antchito.Malo olumikizirawa nthawi zambiri amakhala pafupi kapena pansi pa chosinthira.
Popanga zigawo za magetsi, gwiritsani ntchito njira zonse zamkuwa zomwe zilipo pazigawozi.Ngati n'kotheka, musalole zigawo izi kugawana ma alignments, monga ma alignments owonjezera ndi vias akhoza kuwononga msanga wosanjikiza magetsi pogawanika mu zidutswa zing'onozing'ono.The zotsatira sparse mphamvu wosanjikiza akhoza Finyani njira panopa kumene iwo akufunika kwambiri, ndiye zikhomo mphamvu ya Converter.Kufinya pano pakati pa vias ndi ma alignments amakweza kukana, kuchititsa pang'ono voteji dontho kudutsa zikhomo mphamvu Converter.
Pomaliza, kuyika kwa gawo lamagetsi ndikofunikira.Osayikanso phokoso lamagetsi a digito pamwamba pagawo lamagetsi a analogi, kapena awiriwa atha kukhala ndi banja ngakhale ali pamagulu osiyanasiyana.Pofuna kuchepetsa chiwopsezo cha kuwonongeka kwa magwiridwe antchito, kapangidwe kake kayenera kulekanitsa mitundu iyi ya zigawo m'malo moziyika pamodzi ngati kuli kotheka.
Kodi mapangidwe a PCB's power delivery system (PDS) anganyalanyazidwe?
Cholinga cha mapangidwe a PDS ndikuchepetsa mphamvu yamagetsi yomwe imapangidwa potengera kuchuluka kwa magetsi.Mabwalo onse amafunikira apano, ena omwe amafunikira kwambiri ndipo ena omwe amafunikira kuti aperekedwe mwachangu.Kugwiritsa ntchito mphamvu yocheperako yocheperako yocheperako kapena wosanjikiza wapansi ndi PCB lamination yabwino kumachepetsa kuthamanga kwamagetsi chifukwa chakufunika kwa dera.Mwachitsanzo, ngati mapangidwewo apangidwa kuti azisinthira 1A ndipo kutsekeka kwa PDS ndi 10mΩ, kuchuluka kwamphamvu kwamagetsi ndi 10mV.
Choyamba, mawonekedwe a stack PCB ayenera kupangidwa kuti azithandizira zigawo zazikulu za capacitance.Mwachitsanzo, chigawo chachisanu ndi chimodzi chikhoza kukhala ndi chizindikiro chapamwamba, choyamba chapansi, choyamba cha mphamvu, chachiwiri cha mphamvu, chachiwiri chapansi, ndi chizindikiro chapansi.Gawo loyamba la pansi ndi gawo loyamba lamagetsi limaperekedwa kuti likhale loyandikana wina ndi mzake muzomangamanga zokhazikika, ndipo zigawo ziwirizi zimasiyanitsidwa ndi 2 mpaka 3 mils kuti apange capacitance yamkati.Ubwino waukulu wa capacitor iyi ndikuti ndi yaulere ndipo imangofunika kufotokozedwa muzolemba zopanga PCB.Ngati gawo lamagetsi liyenera kugawidwa ndipo pali njanji zambiri za VDD pagawo lomwelo, gawo lalikulu kwambiri lamagetsi liyenera kugwiritsidwa ntchito.Osasiya mabowo opanda kanthu, komanso samalani ndi mabwalo ovuta.Izi zidzakulitsa mphamvu ya VDD wosanjikiza.Ngati mapangidwewo amalola kukhalapo kwa zigawo zowonjezera, zigawo ziwiri zowonjezera zowonjezera ziyenera kuikidwa pakati pa magawo oyambirira ndi achiwiri a magetsi.Pankhani ya malo omwewo apakati a 2 mpaka 3 mils, mphamvu yachilengedwe ya kapangidwe ka laminated idzawonjezeka kawiri panthawiyi.
Kwa PCB lamination yabwino, decoupling capacitors ayenera kugwiritsidwa ntchito poyambira polowera magetsi wosanjikiza ndi kuzungulira DUT, zomwe zidzatsimikizira kuti PDS impedance ndi yotsika pa ma frequency osiyanasiyana.Kugwiritsa ntchito ma capacitor angapo a 0.001µF mpaka 100µF kumathandizira kuphimba izi.Sikoyenera kukhala ndi ma capacitors kulikonse;ma capacitors molunjika motsutsana ndi DUT adzaphwanya malamulo onse opanga.Ngati pakufunika kutero, derali limakhala ndi mavuto ena.
Kufunika kwa Mapadi Ovumbulutsidwa (E-Pad)
Ichi ndi chinthu chosavuta kunyalanyaza, koma ndikofunikira kuti tikwaniritse magwiridwe antchito abwino kwambiri komanso kutentha kwa kapangidwe ka PCB.
Pad yowonekera (Pin 0) imatanthawuza padi yomwe ili pansi pa ma IC othamanga kwambiri amakono, ndipo ndi kulumikizana kofunikira komwe maziko onse amkati a chip amalumikizidwa ndi malo apakati pansi pa chipangizocho.Kukhalapo kwa pad poyera kumalola otembenuza ambiri ndi amplifiers kuti athetse kufunikira kwa pini yapansi.Chinsinsi ndicho kupanga cholumikizira chokhazikika komanso chodalirika chamagetsi ndi kulumikizidwa kwamafuta mukamangiriza pedi iyi ku PCB, apo ayi dongosololi likhoza kuwonongeka kwambiri.
Kulumikizana koyenera kwa magetsi ndi kutentha kwa mapadi owonekera kumatha kuchitika potsatira njira zitatu.Choyamba, ngati n'kotheka, mapepala owonekera ayenera kutsatiridwa pa PCB iliyonse, yomwe idzapereka kulumikiza kotentha kwa nthaka yonse ndipo motero kutentha kwachangu, makamaka kofunika pazida zamphamvu kwambiri.Kumbali yamagetsi, izi zidzapereka kulumikizana kwabwino kwa equipotential kwa zigawo zonse zoyambira.Pobwereza mapepala owonekera pansi, amatha kugwiritsidwa ntchito ngati malo osakanikirana ndi malo opangira kutentha.
Kenaka, gawani mapepala owonekera m'magawo angapo ofanana.Mawonekedwe a boardboard ndi abwino kwambiri ndipo amatha kupezeka ndi ma grid cross cross kapena masks a solder.Pamsonkhano wa reflow, sizingatheke kudziwa momwe solder phala imayendera kuti ikhazikitse kugwirizana pakati pa chipangizo ndi PCB, kotero kugwirizana kungakhalepo koma kugawidwa mosagwirizana, kapena kuipiraipira, kugwirizana kuli kochepa ndipo kuli pakona.Kugawaniza pad poyera m'zigawo zing'onozing'ono kumalola kuti dera lililonse likhale ndi malo olumikizirana, motero kuonetsetsa kugwirizana kodalirika, ngakhale kugwirizana pakati pa chipangizo ndi PCB.
Pomaliza, ziyenera kutsimikiziridwa kuti gawo lililonse limakhala ndi kulumikizana kwa dzenje kumtunda.Madera nthawi zambiri amakhala akulu mokwanira kuti agwire ma vias angapo.Musanayambe msonkhano, onetsetsani kuti mwadzaza vias iliyonse ndi solder phala kapena epoxy.Sitepe ndi zofunika kuonetsetsa kuti poyera PAD solder phala sikuyenda mmbuyo mu vias cavities, amene mwina kuchepetsa mwayi kugwirizana bwino.
Vuto la kulumikizana pakati pa zigawo mu PCB
M'mapangidwe a PCB, mawayilesi amawaya a otembenuza othamanga kwambiri mosakayikira amakhala ndi gawo limodzi lophatikizana ndi lina.Nthawi zina, wosanjikiza wovuta wa analogi (mphamvu, nthaka, kapena chizindikiro) akhoza kukhala pamwamba pa digito yaphokoso kwambiri.Okonza ambiri amaganiza kuti izi ndizosafunika chifukwa zigawozi zili pamagulu osiyanasiyana.Ndi choncho?Tiyeni tione mayeso osavuta.
Sankhani chimodzi mwa zigawo zoyandikana ndikulowetsa chizindikiro pamlingo umenewo, ndiye, gwirizanitsani zigawo zophatikizana ndi spectrum analyzer.Monga mukuonera, pali zizindikiro zambiri zogwirizana ndi wosanjikiza woyandikana nawo.Ngakhale mutatalikirana ndi 40 mils, pali lingaliro lomwe zigawo zoyandikana zimapangabe capacitance, kotero kuti pamaulendo ena chizindikirocho chimalumikizidwabe kuchokera ku gulu lina kupita ku lina.
Kungoganiza kuti gawo la digito laphokoso lapamwamba pagawo lili ndi chizindikiro cha 1V kuchokera pakusintha kothamanga kwambiri, wosanjikiza wosasunthika adzawona chizindikiro cha 1mV chophatikizidwa kuchokera pagawo loyendetsedwa pomwe kudzipatula pakati pa zigawo ndi 60dB.Kwa 12-bit analog-to-digital converter (ADC) yokhala ndi 2Vp-p full-scale swing, izi zikutanthauza 2LSB (yochepa kwambiri) yolumikizana.Kwa dongosolo lomwe laperekedwa, izi sizingakhale zovuta, koma ziyenera kuzindikirika kuti chigamulochi chikawonjezedwa kuchokera ku 12 mpaka 14 bits, kukhudzidwa kumawonjezeka ndi zina zinayi ndipo motero kulakwitsa kumawonjezeka kufika ku 8LSB.
Kunyalanyaza kugwirizana kwa mtanda / mtanda wosanjikiza sikungalepheretse dongosolo la dongosolo, kapena kufooketsa mapangidwe, koma munthu ayenera kukhala tcheru, chifukwa pangakhale kugwirizana kwakukulu pakati pa zigawo ziwiri kuposa momwe munthu angayembekezere.
Izi ziyenera kuzindikirika pamene phokoso lolumikizana molakwika likupezeka mkati mwazomwe mukufuna.Nthawi zina ma wiring amapangidwe amatha kubweretsa zizindikiro zosayembekezereka kapena kusanjikizana kolumikizana kumagawo osiyanasiyana.Kumbukirani izi mukamakonza machitidwe ovuta: vuto likhoza kukhala pamndandanda pansipa.
Nkhaniyi yachotsedwa pa intaneti, ngati pali kuphwanya kulikonse, chonde lemberani kuti muchotse, zikomo!
Nthawi yotumiza: Apr-27-2022