Basic matambudziko uye hunyanzvi hwekuvandudza pcb dhizaini

Kana tichigadzira PCB, isu tinowanzovimba neruzivo uye nehunyanzvi hwatinowanzo kuwana paInternet. Imwe neimwe pcb dhizaini inogona kukwidziridzwa kune yakatarwa kunyorera. Kazhinji, magadzirirwo ayo mitemo anongoshanda chete kune chakanangwa kunyorera. Semuenzaniso, iyo ADC PCB mitemo haishande kuRF PCBs uye zvinopesana. Nekudaro, mamwe marongero anogona kutariswa akajairwa kune chero pcb dhizaini. Pano, mune ino dzidzo, isu tichaunza mamwe ekutanga matambudziko uye hunyanzvi hunogona zvakanyanya kugadzirisa pcb dhizaini.
Kugovera kwesimba chinhu chakakosha mune chero dhizaini yemagetsi. Zvese zvinhu zvako zvinovimba nesimba kuita mabasa avo. Zvichienderana neyako dhizaini, zvimwe zvinhu zvinogona kuve neakasiyana magetsi kubatana, nepo zvimwe zvinhu zviri pabhodhi rimwe chete zvingave zvisina kusimba magetsi kubatana. Semuenzaniso, kana zvese zvinhu zvikafambiswa neimwe wiring, chimwe nechimwe chikamu chichaona imwe impedance, zvichikonzera kuwanda kwekuratidzira. Semuenzaniso, kana uine maviri maADC macircuit, imwe pakutanga uye imwe kumagumo, uye maADC ese ari maviri achiverenga magetsi ekunze, dunhu rega rega reanalogog richaverenga rakasiyana mukana kune ivo pachavo.
Tinogona kupfupisa kugoverwa kwesimba munzira nhatu dzinogona kuita: imwechete poindi sosi, Nyeredzi sosi uye sosi ye multipoint.
(a) Posi imwechete magetsi emagetsi: magetsi emagetsi uye waya yepasi yechinhu chimwe nechimwe akapatsanurwa kubva kune mumwe nemumwe. Kugadziriswa kwesimba kwezvinhu zvese zvinosangana chete pane imwechete poindi poindi. Pfungwa imwechete inofungidzirwa yakakodzera simba. Nekudaro, izvi hazvigoneke zvemapurojekiti akaomarara kana makuru / ari pakati nepakati.
(b) Nyeredzi sosi: Nyeredzi sosi inogona kutariswa sekuvandudzwa kweimwe poindi sosi. Nekuda kwehunhu hwayo hwakakosha, zvakasiyana: kureba kwekufamba pakati pezvinhu zvakafanana. Nyeredzi kubatanidza inowanzo shandiswa kune akaomarara epamusoro-kumhanya mamaki emabhodhi ane akasiyana mawachi. Mune iyo yekumhanyisa-chiratidzo chiratidzo PCB, iyo chiratidzo inowanzo kubva kubva kumucheto uye yozosvika pakati. Zviratidzo zvese zvinogona kutapurirwa kubva pakati kuenda kune chero nzvimbo yebhodhi redunhu, uye kunonoka pakati penzvimbo kunogona kuderedzwa.
(c) Manyuko enzvimbo dzakawanda: anofungidzirwa kuva murombo mune chero mamiriro ezvinhu. Nekudaro, zviri nyore kushandisa mune chero dunhu. Multipoint masosi anogona kuburitsa mareferenzi misiyano pakati pezvinhu uye mune yakajairwa impedance yekubatanidza. Iyi dhizaini dhizaini zvakare inobvumidza yakakwira switching IC, wachi uye RF maseketi kuunza ruzha mumatunhu ari padyo kugovana kubatana.
Ehezve, muhupenyu hwedu hwezuva nezuva, isu hatichagara tine mhando imwe chete yekugovera. Iyo tradeoff yatinogona kugadzira kusanganisa imwechete poindi sosi neakawanda-mapoinzi sosi. Iwe unogona kuisa michina inonzwisisika yeanalogog uye akakwira-kumhanya / masystem eRF mune imwe poindi, uye nezvimwe zvese zvisinganetsi zvigadzirwa mune imwe poindi.
Wati wambofunga nezve kana uchifanira kushandisa simba ndege? Mhinduro ndeyokuti hungu. Simba bhodhi ndiyo imwe yenzira dzekuchinjisa simba uye kudzikamisa ruzha rwechero dunhu. Ndege yemagetsi inopfupisa nzira yekumhara, inoderedza iyo inductance uye inovandudza magadzirirwo emagetsi (EMC) mashandiro. Izvo zvakare zvakakonzerwa nenyaya yekuti yakafanana ndiro ndiro decoupling capacitor inogadzirwawo mune magetsi magetsi ndege kumativi ese maviri, kuitira kudzivirira ruzha kupararira.
Bhodhi remagetsi zvakare rine mukana wakajeka: nekuda kwenzvimbo yayo hombe, inobvumidza yakawanda yazvino kupfuura, nokudaro ichiwedzera tembiricha yekushanda yePCB. Asi ndapota cherekedza: iyo sosi yemagetsi inogona kusimudzira tembiricha yekushanda, asi iyo wiring inofanirawo kutariswa. Mitemo yekutevera inopihwa ipc-2221 uye ipc-9592
Kune pcbb ine RF sosi (kana chero ipi inomhanya-mhanya chiratidzo application), unofanirwa kunge uine yakakwana ivhu ndege kuti uvandudze mashandiro edunhu redunhu. Zviratidzo zvinofanirwa kunge zviri pane ndege dzakasiyana, uye zvinoita zvisingaite kuzadzikisa zvese zvinodiwa panguva imwe chete uchishandisa matete maviri eplate. Kana iwe uchida kugadzira kanyanga kana chero yakaderera kuomarara RF bhodhi, unogona kushandisa maviri akaturikidzana. Iyi inotevera nhamba inoratidza mufananidzo wekuti PCB yako ingashandise sei zvirinani ndege idzi.
Mukugadzirwa kwemasaini akasanganiswa, vagadziri vanowanzokurudzira kuti pasi yeanalogog ipatsanurwe kubva kudigital pasi. Anonzwisisika masekete eanalogi anokanganiswa nyore nyore neakakwira-mhanyisa switch uye zviratidzo. Kana analoginendi nedigital grounding zvakasiyana, iyo grounding ndege inoparadzaniswa. Nekudaro, ine zvinotevera zvakashata. Isu tinofanirwa kutarisisa kune crosstalk uye loop nzvimbo yeiyo nzvimbo yakakamurwa inokonzerwa zvakanyanya nekumisikidzwa kwendege yepasi. Mufananidzo unotevera unoratidza muenzaniso wenzvimbo mbiri dzakasiyana dzevhu. Kudivi rekuruboshwe, iyo yekudzoka ikozvino haigone kupfuura yakanangana nenzira yechiratidzo, saka pachave nenzvimbo yekutenderera pachinzvimbo chekugadzirwa munzvimbo yekurudyi.
Electromagnetic kuenderana uye remagetsi kupindira (EMI)
Yezve yakakwira frequency dhizaini (senge maRF masisitimu), EMI inogona kuve kusakosha kukuru. Ndege yepasi yakakurukurwa pakutanga inobatsira kudzora EMI, asi zvinoenderana nePCB yako, iyo yepasi ndege inogona kukonzera mamwe matambudziko. Mumaminiti ane mana kana anopfuura marara, chinhambwe chendiza chakakosha kwazvo. Kana iyo capacitance pakati pendege iri diki, munda wemagetsi uchawedzera pabhodhi. Panguva imwecheteyo, iyo impedance pakati pendege mbiri inoderera, ichibvumira iyezvino kudzoka kuyerera kune iyo chiratidzo ndege. Izvi zvinogadzira EMI yechero yakakwira frequency chiratidzo ichipfuura nendege.
Mhinduro yakapusa yekudzivirira EMI ndeyekudzivirira akakwira-mhanyisa masaini kubva pakuyambuka akawanda materu. Wedzera decoupling capacitor; Uye isa nzvimbo yekumisikidza vias yakatenderedza chiratidzo wiring. Iyi inotevera nhamba inoratidza yakanaka PCB dhizaini ine yakakwira frequency chiratidzo.
Filter ruzha
Bypass capacitors uye ferrite maroads ndiwo ma capacitors anoshandiswa kusefa ruzha rwunogadzirwa nechero chinhu. Chaizvoizvo, kana ikashandiswa mune chero inomhanya-mhanya kunyorera, chero iyo I / O pini inogona kuve ruzha sosi. Kuti tishandise zviri nani izvi zvirimo, isu tichafanirwa kutarisa kune anotevera mapoinzi:
Gara uchiisa ferrite marozari uye odarika ma capacitors padhuze sezvinobvira kune ruzha sosi.
Kana isu tichishandisa otomatiki kuisirwa uye otomatiki nzira, isu tinofanirwa kufunga daro rekutarisa.
Dzivisa vias uye chero imwe nzira pakati pe mafirita nezvinhu.
Kana paine ndege yepasi, shandisa akawanda kuburikidza nemakomba kuivhura nemazvo.