I-PCB (iBhodi yeSekethe eShicileleyo), igama lesiTshayina liprintwe ibhodi yesekethe, ekwabizwa ngokuba yibhodi yesekethe eprintiweyo, licandelo elibalulekileyo le-elektroniki, ukuxhasa amacandelo e-elektroniki, kunye nomthwali woqhagamshelo lombane lwamacandelo e-elektroniki.Ngenxa yokuba yenziwe ngokuprintwa kwe-elektroniki, ibizwa ngokuba yibhodi yesekethe "eprintiweyo".
1. Indlela yokukhetha ibhodi yePCB?
Ukhetho lwebhodi yePCB kufuneka lube nolungelelwaniso phakathi kweemfuno zoyilo lokuhlangabezana, imveliso yobuninzi kunye neendleko.Iimfuno zokuyila ziqulethe zombini izinto zombane kunye nezomatshini.Ngokuqhelekileyo lo mba wezinto eziphathekayo ubaluleke kakhulu xa uyilwa iibhodi zePCB ezinesantya esiphezulu (i-frequency enkulu kune GHz).
Ngokomzekelo, izinto ze-FR-4 ezisetyenziswa ngokuqhelekileyo namhlanje zisenokungafaneleki ngenxa yokuba ilahleko ye-dielectric kwi-frequency ye-GHz eziliqela iya kuba nempembelelo enkulu ekunciphiseni umqondiso.Ngokubhekiselele kumbane, kuyimfuneko ukubeka ingqalelo ukuba i-dielectric constant (dielectric constant) kunye nokulahleka kwe-dielectric ifanelekile kwi-frequency eyilelwe.
2. Ukuphepha njani ukuphazamiseka okuphezulu?
Umbono osisiseko wokunqanda ukuphazamiseka okuhamba rhoqo kukunciphisa uphazamiseko lwemimandla yombane we-high-frequency signal, ebizwa ngokuba yi-crosstalk (Crosstalk).Unokwandisa umgama phakathi kwesignali yesantya esiphezulu kunye nesignali ye-analog, okanye ungeze umlindi womhlaba / umkhondo we-shunt ecaleni kwesignali ye-analog.Kwakhona qaphela ukuphazamiseka kwengxolo yomhlaba wedijithali kumhlaba we-analog.
3. Kuyilo lwesantya esiphezulu, indlela yokusombulula ingxaki yengqibelelo yesiginali?
Ingqibelelo yomqondiso ngokusisiseko ngumbandela wokuthelekisa ukuthintela.Izinto ezichaphazela ukuhambelana kwe-impedance zibandakanya ukwakheka kunye nokuphazamiseka kwemveliso yomthombo wesignali, i-impedance yeempawu zomkhondo, iimpawu zokuphela komthwalo, kunye ne-topology yomkhondo.Isisombululo kukuxhomekeka ekupheliseni kunye nokulungelelanisa i-topology ye-wiring.
4. Yenziwa njani indlela yokwahlulahlula ngokwahlukileyo?
Kukho iingongoma ezimbini zokunika ingqalelo kwi-wiring ye-different pair.Enye kukuba ubude bemigca emibini kufuneka bube bubude kangangoko.Kukho iindlela ezimbini ezihambelanayo, enye yeyokuba imigca emibini iqhuba kuluhlu lwe-wiring efanayo (icala-ngecala), kwaye enye imigca emibini iqhuba kumaleko asecaleni angasentla nasezantsi (ngaphezulu-ngaphantsi).Ngokuqhelekileyo, i-side-by-side (icala ngecala, icala ngecala) lisetyenziswa ngeendlela ezininzi.
5. Kumgca wesignali yewotshi enesiphelo sesiphumo esisodwa kuphela, indlela yokuphumeza i-wiring yokwahlukana?
Ukusebenzisa i-wiring yokwahlukana, kunentsingiselo kuphela ukuba umthombo wesignali kunye nomamkeli zimbini iimpawu ezihlukeneyo.Ngoko ke akunakwenzeka ukusebenzisa i-wiring yokwahlukana kwisignali yewotshi enemveliso enye kuphela.
6. Ngaba isichasi esimatanisayo sinokongezwa phakathi kwezibini zemigca yokwahlukana ekupheleni kokufumana?
Ukuchasana okuhambelanayo phakathi kweebini zomgca ohlukeneyo ekupheleni kokufumana ngokuqhelekileyo kufakwe, kwaye ixabiso layo kufuneka lilingane nexabiso le-impedance yokwahlukana.Ngale ndlela umgangatho wesignali uya kuba ngcono.
7. Kutheni i-wiring ye-different pairs kufuneka isondele kwaye ihambelane?
Umzila wezibini ezihlukeneyo kufuneka uvale ngokufanelekileyo kwaye uhambelane.Okubizwa ngokuba kufutshane ngokufanelekileyo kungenxa yokuba umgama uya kuchaphazela ixabiso le-impedance yokwahlukana, okuyiparameter ebalulekileyo yokuyila isibini esahlukileyo.Imfuno yokuhambelana nayo ingenxa yesidingo sokugcina ukuhambelana kwe-impedance yokwahlukana.Ukuba imigca emibini ikude okanye ikufuphi, ukungafani okungafaniyo kuya kuhambelana, okuya kuchaphazela ingqibelelo yesignali (ingqibelelo yesignali) kunye nokulibaziseka kwexesha (ukulibaziseka kwexesha).
8. Ukujongana njani nongquzulwano lwethiyori kwiingcingo zokwenene
Ngokwenene, kulungile ukwahlula umhlaba we-analog / digital.Kufuneka kuqatshelwe ukuba iimpawu zomqondiso akufanele ziwele indawo eyahlulwe (i-moat) kangangoko kunokwenzeka, kwaye indlela yokubuya yangoku (indlela yokubuyisela yangoku) yonikezelo lwamandla kunye nomqondiso akufanele ube mkhulu kakhulu.
I-crystal oscillator yi-analog positive feedback oscillation circuit.Ukuze ube nesignali ye-oscillation ezinzileyo, kufuneka ihlangabezane neenkcukacha zokufumana i-loop kunye nesigaba.Nangona kunjalo, ukucaciswa kwe-oscillation yalo mqondiso we-analog kuphazamiseka ngokulula, kwaye kunye nokongeza imikhondo yokugada komhlaba ayinakukwazi ukwahlula ngokupheleleyo ukuphazamiseka.Kwaye ukuba ikude kakhulu, ingxolo kwi-plane yomhlaba iya kuchaphazela kwakhona i-feedback oscillation circuit.Ngoko ke, umgama phakathi kwe-crystal oscillator kunye ne-chip kufuneka ube kufutshane ngokusemandleni.
Ewe, zininzi iingxabano phakathi kwendlela enesantya esiphezulu kunye neemfuno ze-EMI.Kodwa umgaqo osisiseko kukuba resistors kunye capacitors okanye amaso ferrite ezongeziweyo ngenxa EMI ayinakubangela ezinye iimpawu zombane uphawu ukusilela ukuhlangabezana neenkcukacha.Ngoko ke, kungcono ukusebenzisa ubuchule bokucwangcisa i-wiring kunye ne-PCB stacking ukusombulula okanye ukunciphisa iingxaki ze-EMI, ezifana nokuhambisa imiqondiso yesantya esiphezulu ukuya kumaleko angaphakathi.Ekugqibeleni, sebenzisa i-resistor capacitor okanye i-ferrite bead ukunciphisa umonakalo kwisignali.
9. Indlela yokusombulula ukuchasana phakathi kwe-wiring ye-manual kunye ne-wiring ezenzekelayo yeempawu zesantya esiphezulu?
Uninzi lweendlela ezizenzekelayo zesoftware eyomeleleyo ngoku zibeke imithintelo yokulawula indlela yokuqhuba kunye nenani le-vias.Ukusetwa kwezinto zobuchule be-injini ejikelezayo kunye neemeko zoxinzelelo lweenkampani ezahlukeneyo ze-EDA ngamanye amaxesha zahluka kakhulu.
Ngokomzekelo, ngaba kukho imiqobo eyaneleyo yokulawula indlela iinyoka zenyoka, ngaba izithuba zeebini ezihlukeneyo zingalawulwa, njalo njalo.Oku kuyakuchaphazela ukuba indlela yomzila efunyenwe ngokuzenzekela iyakwazi ukuhlangabezana nombono womyili.
Ukongeza, ubunzima bokulungelelanisa ngesandla i-wiring bubuye bube nobudlelwane obupheleleyo kunye nekhono le-injini yokucima.Umzekelo, ukutyhala umkhondo, ukutyhala nge-vias, kunye nokunyanzeliswa kweempawu kubhedu, njl njl. Ngoko ke, ukukhetha i-router enegunya elinamandla le-injini yokujija isisombululo.
10. Malunga namakhuphoni ovavanyo.
Ikhuphoni yokuvavanya isetyenziselwa ukulinganisa ukuba i-impedance yeempawu ze-PCB evelisiweyo ihlangabezana neemfuno zoyilo kunye ne-TDR (i-Time Domain Reflectometer).Ngokuqhelekileyo, i-impedance ekufuneka ilawulwe inamatyala amabini: umgca omnye kunye nesibini esahlukileyo.Ngoko ke, ububanzi bomgca kunye nemigca yomgca (xa kukho izibini ezihlukeneyo) kwikhuphoni yokuvavanya kufuneka ifane nemigca ekufuneka ilawulwe.
Eyona nto ibaluleke kakhulu yindawo yendawo yomhlaba xa ulinganisa.Ukuze kuncitshiswe ixabiso le-inductance ye-lead yomhlaba (i-lead yomhlaba), indawo apho i-TDR probe (probe) isekelwe khona idla ngokukufutshane kakhulu kwindawo apho umqondiso ulinganiswa khona (i-probe tip).Ke ngoko, umgama kunye nendlela phakathi kwendawo apho umqondiso ulinganiswa kwikhuphoni yovavanyo kunye nendawo yomhlaba Ukutshatisa iprobe esetyenzisiweyo.
11. Kuyilo lwe-PCB olunesantya esiphezulu, indawo engenanto yoluhlu lwesiginali inokugqunywa ngobhedu, kodwa kufuneka ubhedu lwemigangatho yemiqondiso emininzi lusasazwe njani phantsi kunye nonikezelo lwamandla?
Ngokuqhelekileyo, ininzi yobhedu kwindawo engenanto iphantsi.Mane unikele ingqalelo kumgama phakathi kobhedu kunye nomgca wesignali xa ubeka ubhedu ecaleni komgca wesignali yesantya esiphezulu, kuba ubhedu olugciniweyo luya kunciphisa i-impedance yeempawu zomkhondo omncinci.Ulumke kananjalo ungachaphazeli uphawu lwezinye iileya, njengakulwakhiwo lwemigca emibini.
12. Ngaba kunokwenzeka ukusebenzisa imodeli yomgca we-microstrip ukubala i-impedance yeempawu zomgca wesignali ngaphezu kwendiza yamandla?Ngaba umqondiso phakathi kwamandla kunye nenqwelomoya ephantsi ingabalwa kusetyenziswa imodeli yestripline?
Ewe, zombini inqwelomoya yamandla kunye nenqwelomoya ephantsi kufuneka ithathelwe ingqalelo njengeenqwelo-moya zesalathiso xa kubalwa i-impedance yeempawu.Umzekelo, ibhodi enemigangatho emine: umaleko ophezulu-umgangatho ophezulu-umhlaba umaleko-ophantsi.Ngeli xesha, imodeli ye-impedance yeempawu zomkhondo we-top layer yimodeli yomgca we-microstrip kunye nendiza yamandla njengendiza yereferensi.
13. Ngokubanzi, ngaba ukuveliswa ngokuzenzekelayo kwamanqaku ovavanyo ngesoftware kwiibhodi eziprintiweyo eziphezulu zihlangabezana neemfuno zovavanyo lwemveliso yobuninzi?
Ingaba amanqaku ovavanyo aveliswa ngokuzenzekelayo yisoftware ngokubanzi ahlangabezana neemfuno zovavanyo kuxhomekeke ekubeni iinkcukacha zokongeza amanqaku ovavanyo ziyahlangabezana neemfuno zezixhobo zovavanyo.Ukongeza, ukuba i-wiring ixinene kakhulu kwaye ukucaciswa kokongeza amanqaku okuvavanya kungqongqo, akunakukwazi ukongeza ngokuzenzekelayo amanqaku ovavanyo kwicandelo ngalinye lomgca.Kakade ke, kuyimfuneko ukuba ugcwalise ngesandla kwiindawo eziza kuvavanywa.
14. Ngaba ukongezwa kwamanqaku okuvavanya kuya kuchaphazela umgangatho weempawu zesantya esiphezulu?
Ngokumalunga nokuba kuya kuchaphazela umgangatho wesignali, kuxhomekeke kwindlela yokongeza amanqaku okuvavanya kunye nokukhawuleza kwesibonakaliso.Ngokwenene, amanqaku ovavanyo olongezelelweyo (ungasebenzisi i-pin ekhoyo okanye i-DIP njengamanqaku okuvavanya) anokongezwa kumgca okanye akhutshwe kumgca.Eyangaphambili ilingana nokongeza i-capacitor encinci kwi-intanethi, ngelixa le yokugqibela isebe elongezelelweyo.
Ezi meko zimbini ziya kuchaphazela umqondiso wesantya esiphezulu ngaphezulu okanye ngaphantsi, kwaye inqanaba lempembelelo linxulumene nesantya sesantya somqondiso kunye nesantya somda wesignali (umda wesantya).Ubungakanani bempembelelo bukwaziwa ngokulinganisa.Ngokomgaqo, incinci indawo yokuvavanya, ingcono (ngokuqinisekileyo, kufuneka ihlangabezane neemfuno zezixhobo zokuvavanya).Isebe lifutshane, lingcono.
15. IiPCB ezininzi zenza inkqubo, kufuneka zidityaniswe njani iingcingo zomhlaba phakathi kweebhodi?
Xa umqondiso okanye amandla phakathi kweebhodi ezahlukeneyo PCB eqhagamshelwe omnye komnye, umzekelo, ibhodi A inamandla okanye imiqondiso ithunyelwe kwibhodi B, kufuneka kubekho inani elilinganayo langoku eliqukuqelayo ukusuka umaleko emhlabeni ubuyela kwibhodi A (le Kirchoff umthetho wangoku).
Ikhoyo ngoku kolu qulunqo iya kufumana indawo yokuchasana okuncinci ukuhamba ngasemva.Ngoko ke, inani lezikhonkwane ezinikezelwe kwindiza yomhlaba akufanele libe lincinci kakhulu kwi-interface nganye, kungakhathaliseki ukuba ngumbane okanye umqondiso, ukwenzela ukuba kuncitshiswe i-impedance, enokunciphisa ingxolo kwi-plane yomhlaba.
Ukongeza, kunokwenzeka kwakhona ukuhlalutya yonke i-loop yangoku, ngokukodwa inxalenye enomsinga omkhulu, kwaye ulungelelanise indlela yokudibanisa yokwakheka okanye ucingo lomhlaba ukulawula ukuhamba kwangoku (umzekelo, ukudala i-impedance ephantsi kwenye indawo, ukuze uninzi lokuqukuqela kwangoku ukusuka kwezi ndawo), nciphisa impembelelo kwezinye iimpawu ezinovakalelo.
16. Ngaba ungazisa ezinye iincwadi zobugcisa zangaphandle kunye nedatha kwi-high-speed PCB design?
Ngoku iisekethe zedijithali ezikhawulezayo zisetyenziswa kwiinkalo ezinxulumeneyo ezifana nothungelwano lonxibelelwano kunye neekhaltyhuleyitha.Ngokubhekiselele kuthungelwano lonxibelelwano, ukusebenza rhoqo kwebhodi ye-PCB ifikelele kwi-GHz, kwaye inani leeleya ezipakishweyo zininzi kangangoko ndikwaziyo.
Usetyenziso olunxulumene nekhaltyhuleyitha lukwangenxa yokuqhubela phambili kweetships.Ingaba i-PC jikelele okanye iseva (Umncedisi), i-frequency ephezulu yokusebenza kwibhodi nayo ifikelele kwi-400MHz (njengeRambus).
Ukuphendula kwiimfuno zendlela ezihamba ngesantya esiphezulu kunye noxinaniso oluphezulu, imfuno yeendlela ezingaboniyo / ezingcwatywayo, ii-mircrovias kunye neteknoloji yenkqubo yokwakha iyanda ngokuthe ngcembe.Ezi mfuno zoyilo ziyafumaneka kwimveliso yobuninzi ngabavelisi.
17. Iifomyula ezimbini ezisoloko zibhekiselwa kwimpawu zokuthintela:
Umgca weMicrostrip (microstrip) Z={87/[sqrt(Er+1.41)]}ln[5.98H/(0.8W+T)] apho uW bububanzi bomgca, T bubunzima bobhedu lomkhondo, kunye noH Umgama ukusuka kumkhondo ukuya kwinqwelomoya yesalathiso, i-Er yi-dielectric constant ye-PCB material (dielectric constant).Le fomula inokusetyenziswa kuphela xa 0.1≤(W/H)≤2.0 kunye 1≤(Er)≤15.
I-Stripline (i-stripline) Z=[60/sqrt(Er)]ln{4H/[0.67π(T+0.8W)]} apho, H ngumgama phakathi kweenqwelo-moya ezimbini zesalathiso, kwaye umkhondo umi kumbindi we ezi nqwelo-moya zimbini .Le fomula inokusetyenziswa kuphela xa i-W/H≤0.35 kunye ne-T/H≤0.25.
18. Ngaba ucingo olusezantsi lungongezwa phakathi komgca wesignali yokwahlukana?
Ngokuqhelekileyo, ucingo lomhlaba alukwazi ukufakwa phakathi komqondiso wokuhlukana.Ngenxa yokuba eyona ngongoma ibalulekileyo yomgaqo-nkqubo wesicelo seempawu zokwahlukana kukuthatha inzuzo yeenzuzo eziziswa ngokubambisana (ukudibanisa) phakathi kweempawu ezihlukeneyo, ezifana nokuchithwa kwe-flux, i-immunity immunity, njl. Ukuba ucingo lomhlaba longezwa phakathi, umphumo wokudibanisa uya kutshatyalaliswa.
19. Ngaba uyilo lwebhodi elukhuni-flex lufuna isoftware yoyilo olulodwa kunye neenkcukacha?
Isekethe eprintiweyo eguquguqukayo (FPC) inokuyilwa kunye nesoftware yoyilo lwePCB ngokubanzi.Kwakhona sebenzisa ifomathi yeGerber ukuvelisa abavelisi beFPC.
20. Uthini umgaqo wokukhetha ngokufanelekileyo indawo yokumisa i-PCB kunye necala?
Umgaqo wokukhetha indawo ephantsi ye-PCB kunye negobolondo kukusebenzisa umhlaba we-chassis ukubonelela indlela ephantsi ye-impedance ye-return current (i-returning current) kunye nokulawula indlela ye-return current.Umzekelo, ngokuqhelekileyo kufutshane nesixhobo esinesantya esiphezulu okanye ijenereyitha yewotshi, umaleko osemhlabeni we-PCB unokudityaniswa nomhlaba we-chassis ngokulungisa izikrufu ukuze kuncitshiswe ummandla welophu yangoku, ngaloo ndlela kuncitshiswe imitha ye-electromagnetic radiation.
21. Yeyiphi imiba ekufuneka siqale ngayo kwibhodi yesekethe DEBUG?
Ngokubhekiselele kwiisekethe zedijithali, okokuqala qaphela izinto ezintathu ngokulandelelana:
1. Qinisekisa ukuba onke amaxabiso obonelelo anobungakanani boyilo.Ezinye iisistim ezinobonelelo lwamandla amaninzi zinokufuna iinkcukacha ezithile zolandelelwano kunye nesantya sobonelelo lwamandla athile.
2. Qinisekisa ukuba zonke iifrikhwensi zomqondiso wewotshi zisebenza ngokufanelekileyo kwaye akukho miba ingeyiyo i-monotonic kwiincam zomqondiso.
3. Qinisekisa ukuba isignali yokusetha ngokutsha ihlangabezana neemfuno zokucaciswa.Ukuba zonke ezi ziqhelekileyo, i-chip kufuneka ithumele umqondiso womjikelezo wokuqala (umjikelo).Okulandelayo, debug ngokomgaqo wokusebenza kwenkqubo kunye neprotocol yebhasi.
22. Xa ubungakanani bebhodi yesekethe bulungisiwe, ukuba imisebenzi engaphezulu ifuna ukufakwa kuyilo, kudla ngokuba yimfuneko ukuba kwandiswe ukuxinana komkhondo wePCB, kodwa oku kunokukhokelela ekuphazamisekeni konxibelelwano oluphuculweyo lokulandela umkhondo, kwaye ngexesha elinye. kwangaxeshanye, umkhondo ubhityile kakhulu ukunyusa impedance.Ayinakuthotywa, nceda iingcali zazise izakhono kwi-high-speed (≥100MHz) uyilo lwePCB yoxinaniso oluphezulu?
Xa uyila i-PCB enesantya esiphezulu kunye noxinaniso oluphezulu, ukuphazamiseka kwe-crosstalk kufuneka kunikwe ingqwalasela ekhethekileyo kuba kunempembelelo enkulu kwixesha kunye nengqibelelo yomqondiso.
Nazi izinto ezimbalwa ekufuneka uziqwalasele:
Lawula ukuqhubela phambili kunye nokutshatisa i-trace character impedance.
Ubungakanani besithuba somkhondo.Ngokuqhelekileyo, isithuba esihlala sibonwa siphinda kabini ububanzi bomgca.Impembelelo yesithuba somkhondo kwixesha kunye nemfezeko yomqondiso inokwaziwa ngokulinganisa, kwaye isithuba esincinci esinyamezelekayo sinokufunyanwa.Iziphumo zinokwahluka ukusuka kwitshiphu ukuya kwitshiphu.
Khetha indlela efanelekileyo yokuphelisa.
Gwema ulwalathiso olufanayo lwemikhondo kumaleko angaphezulu nasezantsi akufuphi, okanye udibane nemigca ephezulu nangaphantsi, kuba olu hlobo lwe-crosstalk lukhulu kunolo lwemikhondo ekufutshane kumaleko afanayo.
Sebenzisa iindlela ezingaboniyo/ezingcwatywayo ukwandisa indawo yokulandela umkhondo.Kodwa iindleko zokwenziwa kwebhodi yePCB ziya kunyuka.Kunzima ngokwenene ukufezekisa ukuhambelana okupheleleyo kunye nobude obulinganayo ekuphunyezweni okwenyani, kodwa kuseyimfuneko ukwenza oko kangangoko kunokwenzeka.
Ukongeza, ukupheliswa kokwahluka kunye nokupheliswa kwendlela eqhelekileyo kunokugcinelwa ukuthomalalisa impembelelo kwixesha kunye nemfezeko yomqondiso.
23. Icebo lokucoca kumbane we-analog lihlala liyisekethe yeLC.Kodwa kutheni ngamanye amaxesha iLC izihluza ngaphantsi ngempumelelo RC?
Ukuthelekiswa kwe-LC kunye nemiphumo yokucoca i-RC kufuneka kuthathelwe ingqalelo ukuba i-frequency band iya kuhluzwa kunye nokukhethwa kwexabiso le-inductance lifanelekile.Ngenxa yokuba i-reactance inductive (i-reactance) ye-inductor ihambelana nexabiso le-inductance kunye nokuphindaphinda.
Ukuba i-frequency yengxolo yonikezelo lwamandla iphantsi kwaye ixabiso le-inductance alikho likhulu ngokwaneleyo, umphumo wokucoca unokungabi kuhle njenge-RC.Nangona kunjalo, ixabiso lokuhlawula ukusebenzisa i-RC yokucoca kukuba i-resistor ngokwayo ichitha amandla, ayisebenzi kakuhle, kwaye inika ingqalelo ukuba ingakanani amandla okumelana nokukhethwa.
24. Ithini indlela yokukhetha i-inductance kunye nexabiso le-capacitance xa ukucoca?
Ukongeza kwi-frequency yengxolo ofuna ukuyicoca ngaphandle, ukhetho lwexabiso le-inductance lukwathathela ingqalelo isakhono sokuphendula sangoku kwangoko.Ukuba i-terminal ephumayo ye-LC inethuba lokukhupha i-current enkulu ngokukhawuleza, ixabiso elikhulu kakhulu le-inductance liya kuthintela isantya sombane omkhulu ohamba nge-inductor kunye nokwandisa ingxolo ye-ripple.Ixabiso le-capacitance lihambelana nobukhulu bexabiso lenkcazo yengxolo enokunyamezela.
Incinci imfuno yexabiso lengxolo ye-ripple, inkulu ixabiso le-capacitor.I-ESR / ESL ye-capacitor iya kuba nefuthe.Ukongezelela, ukuba i-LC ifakwe kwi-output of the switching regulation power, kukwafuneka ukuba ubeke ingqalelo kwimpembelelo yesibonda / i-zero eyenziwa yi-LC ekuzinzeni kwe-loop yolawulo olubi..
25. Indlela yokuhlangabezana neemfuno ze-EMC kangangoko kunokwenzeka ngaphandle kokubangela uxinzelelo olubi kakhulu lweendleko?
Indleko eyongeziweyo ngenxa ye-EMC kwi-PCB idla ngenxa yokwanda kwenani leengqimba zomhlaba zokuphucula impembelelo yokukhusela kunye nokongezwa kwe-ferrite bead, ukuminxa kunye nezinye izixhobo zokucinezela i-harmonic ye-high-frequency.Ukongezelela, ngokuqhelekileyo kuyimfuneko ukusebenzisana nezakhiwo zokukhusela kwezinye iindlela zokwenza inkqubo yonke idlule iimfuno ze-EMC.Ezi zilandelayo ziingcebiso ezimbalwa zoyilo lwebhodi yePCB zokunciphisa isiphumo semitha ye-electromagnetic eyenziwe yisekethe.
Khetha isixhobo esinesantya esicothayo sokubulala kangangoko unakho ukunciphisa izakhi zefrikhwensi ephezulu eyenziwe ngumqondiso.
Nika ingqalelo ekubekweni kwamacandelo aphezulu-frequency, engasondeli kakhulu kwizixhumi zangaphandle.
Nikelani ingqalelo kwi-impedance ehambelana neempawu zesantya esiphezulu, i-wiring layer kunye nendlela yokubuya kwayo yangoku (ukubuyisela indlela yangoku) ukunciphisa ukubonakaliswa kwe-high-frequency kunye ne-radiation.
Beka i-decoupling capacitors eyaneleyo kunye nefanelekileyo kwizikhonkwane zamandla zesixhobo ngasinye ukumodareyitha ingxolo kumandla kunye neenqwelomoya zomhlaba.Nika ingqalelo ekhethekileyo ukuba ngaba ukuphendulwa rhoqo kunye neempawu zokushisa ze-capacitor zihlangabezana neemfuno zoyilo.
Umhlaba okufutshane nomdibaniso wangaphandle unokwahlulwa ngokufanelekileyo ekubunjweni, kwaye umhlaba wesiqhagamshelo kufuneka uxhunywe kumhlaba we-chassis okufutshane.
Sebenzisa ngokufanelekileyo umlindi womhlaba/umkhondo we-shunt ecaleni kwemiqondiso ethile enesantya esiphezulu.Kodwa nikela ingqalelo kwisiphumo somlindi/umkhondo we-shunt kuphawu lokuthintela umkhondo.
Uluhlu lwamandla luyi-20H ngaphakathi kunokwakheka, kwaye i-H ngumgama phakathi komgangatho wamandla kunye nokwakheka.
26. Xa kukho iibhloko ezininzi zedijithali / ze-analog kwibhodi enye ye-PCB, into eqhelekileyo kukuhlula umhlaba wedijithali / we-analog.Siyintoni isizathu?
Isizathu sokwahlula umhlaba wedijithali / we-analog kukuba isekethe yedijithali iya kuvelisa ingxolo kumandla ombane kunye nomhlaba xa utshintshela phakathi kwamandla aphezulu kunye aphantsi.Ubungakanani bengxolo bunxulumene nesantya somqondiso kunye nobukhulu bangoku.Ukuba inqwelomoya yomhlaba ayahlulwanga kwaye ingxolo eyenziwa yisekethe kwindawo yedijithali inkulu kwaye isiphaluka kwindawo ye-analog isondele kakhulu, ngoko nokuba idijithali kunye nemiqondiso ye-analog ayinqumli, umqondiso we-analog usaza kuphazamiseka. ngengxolo yomhlaba.Oko kukuthi, indlela yokungahluli indawo yedijithali kunye ne-analog ingasetyenziselwa kuphela xa indawo yesiphaluka se-analog ikude nommandla wesekethe yedijithali eyenza ingxolo enkulu.
27. Enye indlela kukuqinisekisa ukuba i-digital / analog layout eyahlukileyo kunye nemigca yesignali yedijithali / ye-analog ayiphambanisi, yonke ibhodi ye-PCB ayahlulwe, kwaye umhlaba wedijithali / we-analog uqhagamshelwe kule nqwelomoya.Inceda ngantoni?
Imfuno yokuba ulandelelwano lwedijithali-analogu umqondiso awukwazi ukuwela kungenxa yokuba indlela yangoku yokubuya (indlela yangoku yokubuya) yomqondiso wedijithali okhawuleza kancinci uya kuzama ukuqukuqela ubuyela kumthombo womqondiso wedijithali ecaleni komhlaba kufutshane nomzantsi womkhondo.ukuwela, ingxolo eveliswa yimbuyekezo yangoku iya kubonakala kwindawo yesiphaluka se-analog.
28. Uyithathela ingqalelo njani ingxaki yokudibanisa i-impedance xa uyila umzobo weskim soyilo lwePCB enesantya esiphezulu?
Xa uyila iisekethe zePCB ezinesantya esiphezulu, ukuthelekisa i-impedance yenye yezinto zoyilo.Ixabiso le-impedance linobudlelwane obupheleleyo kunye nendlela yomzila, njengokuhamba kwi-surface layer (microstrip) okanye i-inner layer (i-stripline / i-stripline ephindwe kabini), umgama ukusuka kuluhlu lwereferensi (umaleko wamandla okanye umaleko womhlaba), ukulandelela ububanzi, i-PCB Izinto eziphathekayo, njl.njl. Zombini ziya kuchaphazela ixabiso leempawu zokuthintela umkhondo.
Oko kukuthi, ixabiso le-impedance linokumiselwa kuphela emva kwe-wiring.I-software yokulinganisa ngokubanzi ayiyi kukwazi ukuqwalasela iimeko ezithile ze-wiring kunye ne-impedance engapheliyo ngenxa yokunciphisa imodeli yomgca okanye i-algorithm yemathematika esetyenzisiweyo.Ngeli xesha, kuphela ezinye iiterminators (ukupheliswa), ezifana nezichasi zothotho, zinokugcinwa kumzobo weskimu.ukunciphisa isiphumo sokulandela ukungaqhubeki kwe-impedance.Esona sisombululo sisisiseko kwingxaki kukuzama ukunqanda ukungaqhubeki kwe-impedance xa ufaka iintambo.
29. Ndingalibonelela phi ithala leencwadi lemodeli ye-IBIS echanekileyo?
Ukuchaneka komzekelo we-IBIS kuchaphazela ngokuthe ngqo iziphumo zokulinganisa.Ngokusisiseko, i-IBIS inokuthathwa njengedatha yeempawu zombane zesekethe elinganayo ye-chip ye-I/O buffer, enokufunyanwa ngokubanzi ngokuguqula imodeli ye-SPICE, kwaye idatha ye-SPICE inobudlelwane obupheleleyo kunye nokuveliswa kwetshiphu, ngoko ke. isixhobo esifanayo sinikezelwa ngabavelisi beetshiphu abohlukeneyo.Idatha kwi-SPICE iyahluka, kwaye idatha kwimodeli ye-IBIS eguqulwayo nayo iya kwahluka ngokufanelekileyo.
Oko kukuthi, ukuba izixhobo zomenzi A zisetyenzisiweyo, kuphela banakho ukubonelela ngedatha yemodeli echanekileyo yezixhobo zabo, kuba akukho mntu uyazi ngcono kunabo ukuba yeyiphi inkqubo eyenziwe ngayo izixhobo zabo.Ukuba i-IBIS ebonelelwe ngumenzi ayichanekanga, isisombululo kuphela kukucela ngokuqhubekayo umenzi ukuba aphucule.
30. Xa uyila ii-PCB ezinesantya esiphezulu, zeziphi iinkalo ekufuneka abaqulunqi baqwalasele imithetho ye-EMC kunye ne-EMI?
Ngokubanzi, uyilo lwe-EMI/EMC kufuneka luthathele ingqalelo yomibini imiba enemitha neqhutywayo.Eyangaphambili yeyaphezulu inxalenye yefrikhwensi (≥30MHz) kwaye yamva yeyommandla ophantsi ojikelezayo (≤30MHz).
Ke awungekhe uhoye i-frequency ephezulu kwaye ungayihoyi indawo ephantsi.Uyilo olulungileyo lwe-EMI/EMC kufuneka luthathele ingqalelo indawo yesixhobo, ulungiselelo lwesitaki sePCB, indlela yoxhulumaniso olubalulekileyo, ukukhethwa kwesixhobo, njl njl ekuqaleni koyilo.Ukuba akukho lungiselelo elingcono kwangaphambili, linokusonjululwa emva koko Kuya kufumana umphumo ophindwe kabini ngesiqingatha somzamo kunye nokwandisa iindleko.
Ngokomzekelo, indawo yejenereyitha yewotshi akufanele isondele kwikhonkco yangaphandle kangangoko kunokwenzeka, umqondiso wesantya esiphezulu kufuneka uye kumaleko angaphakathi kangangoko kunokwenzeka kwaye ubeke ingqalelo ekuqhubekeni kophawu oluhambelanayo kunye Umaleko wereferensi ukunciphisa imbonakalo, kunye nethambeka (isantya esibiyelweyo) sophawu olutyhalwe sisixhobo kufuneka lube luncinci kangangoko ukunciphisa oluphakamileyo ingxolo yendiza yamandla.
Ukongezelela, nikela ingqalelo kwindlela yokubuya ye-high-frequency signal current ukuze wenze indawo ye-loop ibe yincinci kangangoko (oko kukuthi, i-impedance ye-loop incinci kangangoko kunokwenzeka) ukunciphisa imisebe.Kwakhona kunokwenzeka ukulawula uluhlu lwengxolo ephezulu-frequency ngokwahlula ukubunjwa.Ekugqibeleni, khetha ngokufanelekileyo indawo yokumisa ye-PCB kunye necala (umhlaba we-chassis).
31. Unokukhetha njani izixhobo ze-EDA?
Kwi-software yoyilo lwe-pcb yangoku, uhlalutyo lwe-thermal alukho inqaku elinamandla, ngoko ke akukhuthazwa ukuba uyisebenzise.Kweminye imisebenzi 1.3.4, unokukhetha i-PADS okanye i-Cadence, kwaye umlinganiselo wokusebenza kunye nexabiso lilungile.Abaqalayo kwi-PLD yokuyila banokusebenzisa indawo edibeneyo ebonelelwa ngabavelisi be-chip ye-PLD, kunye nezixhobo ze-single-point zingasetyenziswa xa kuyila amasango angaphezu kwesigidi esinye.
32. Kucelwa ucebise nge-software ye-EDA efanele ukusetyenzwa nokuhanjiswa komqondiso onesantya esiphezulu.
Uyilo lwesekethe oluqhelekileyo, i-PADS ye-INNOVEDA ilungile kakhulu, kwaye kukho isoftware yokulinganisa ukulinganisa, kwaye olu hlobo loyilo luhlala lubalelwa kwi-70% yezicelo.Ukuyila i-high-speed circuit circuit, i-analog kunye ne-digital mix circuits, isisombululo se-Cadence kufuneka sibe yi-software esebenza kakuhle kunye nexabiso.Ewe, ukusebenza kweMentor kusekuhle kakhulu, ngakumbi ulawulo lwenkqubo yoyilo kufuneka lube lolona lubalaseleyo.
33. Inkcazo yentsingiselo yomaleko ngamnye webhodi yePCB
I-Topoverlay-- igama lesixhobo somgangatho ophezulu, esikwabizwa ngokuba yi-silkscreen ephezulu okanye i-legend yecandelo eliphezulu, njenge-R1 C5,
I-IC10.bottomoverlay-ngokufanayo i-multilayer--Ukuba uyila ibhodi ene-4-layer, ubeka i-pad yamahhala okanye nge-, ichaze njenge-multilay, i-pad yayo iya kuvela ngokuzenzekelayo kwiileya ezi-4, ukuba Uyichaza kuphela njengomaleko ophezulu, ke ipad yayo iya kuvela kuphela kumaleko aphezulu.
34. Yeyiphi imiba ekufuneka inikwe ingqwalasela kuyilo, umzila kunye noyilo lwee-PCB zefrikhwensi ephezulu ngaphezulu kwe-2G?
Ii-PCB ezikwi-frequency ephezulu ngaphezulu kwe-2G zezoyilo lweesekethe zamaza kanomathotholo, kwaye azikho ngaphakathi kwendawo yengxoxo yoyilo lwesekethe yedijithali enesantya esiphezulu.Uyilo kunye nendlela ye-RF yesekethe kufuneka ithathelwe ingqalelo kunye nedayagram yeskim, kuba uyilo kunye nendlela iya kubangela iziphumo zokusasazwa.
Ngaphaya koko, ezinye izixhobo zokwenziwa kuyilo lwesekethe ye-RF ziphunyezwa ngengcaciso yeparametric kunye nefoyile yobhedu enobume obukhethekileyo.Ngoko ke, izixhobo ze-EDA zifunekayo ukubonelela ngezixhobo zeparametric kwaye uhlele i-foil yobhedu ekhethekileyo.
Isikhululo sebhodi yeMentor sinemodyuli yoyilo yeRF ezinikeleyo ehlangabezana nezi mfuno.Ngapha koko, uyilo oluqhelekileyo lwerediyo lufuna izixhobo ezikhethekileyo zohlalutyo lwesekethe yerediyo, eyona idumileyo kwishishini yi-eesoft ye-agilent, enonxibelelwano oluhle kunye nezixhobo ze-Mentor.
35. Kuyilo lwePCB olukwi-frequency ephezulu ngaphezulu kwe-2G, yeyiphi imigaqo ekufuneka uyilandele uyilo lwe-microstrip?
Kuyilo lweelayini zeRF microstrip, kuyimfuneko ukusebenzisa izixhobo zokuhlalutya intsimi ye-3D ukukhupha iiparamitha zemigca yothumelo.Yonke imigaqo kufuneka icaciswe kwesi sixhobo sokutsalwa kwentsimi.
36. Kwi-PCB enazo zonke iimpawu zedijithali, kukho umthombo wewotshi ye-80MHz ebhodini.Ukongeza ekusebenziseni i-wire mesh (i-grounding), luhlobo luni lwesekethe ekufuneka lusetyenziselwe ukukhusela ukuze kuqinisekiswe ukukwazi ukuqhuba ngokwaneleyo?
Ukuqinisekisa ukukwazi ukuqhuba iwashi, akufanele kuphunyezwe ngokukhuselwa.Ngokuqhelekileyo, iwotshi isetyenziselwa ukuqhuba itshiphu.Inkxalabo ngokubanzi malunga nekhono lokuqhuba iwotshi ibangelwa yimithwalo yeewotshi ezininzi.I-chip yomqhubi wewotshi isetyenziselwa ukuguqula isignali yewotshi enye ibe ezininzi, kwaye uxhulumaniso lwe-point-to-point luyamkelwa.Xa ukhetha i-chip yomqhubi, ukongeza ekuqinisekiseni ukuba ngokusisiseko ihambelana nomthwalo kunye nomgca wesignali uhlangabezana neemfuno (ngokubanzi, iwashi ngumqondiso osebenzayo), xa ubala ixesha lenkqubo, ukulibaziseka kwewashi kumqhubi. chip kufuneka kuthathelwe ingqalelo.
37. Ukuba kusetyenziswe ibhodi yomqondiso wewotshi eyahlukileyo, luhlobo luni lojongano olusetyenziswa ngokubanzi ukuqinisekisa ukuba ukuhanjiswa komqondiso wewotshi kuchaphazeleka kancinci?
Okukhona umfutshane uphawu lwewotshi, kokukhona usiba mncinci isiphumo somgca wothumelo.Ukusebenzisa ibhodi yomqondiso wewotshi eyahlukileyo kuya kwandisa ubude bomzila womqondiso.Kwaye unikezelo lwamandla omhlaba webhodi lukwayingxaki.Ukuhanjiswa komgama omde, kucetyiswa ukuba kusetyenziswe imiqondiso eyahlukileyo.Ubungakanani be-L bunokuhlangabezana neemfuno zomthamo wokuqhuba, kodwa iwotshi yakho ayikhawulezi kakhulu, ayiyomfuneko.
I-38, i-27M, i-SDRAM clock line (80M-90M), i-harmonics yesibini neyesithathu yale migca yewotshi ikwi-band ye-VHF, kwaye ukuphazamiseka kukhulu kakhulu emva kokuba i-frequency ephezulu ingena ukusuka ekupheleni kokufumana.Ukongeza ekucutheni ubude bomgca, zeziphi ezinye iindlela ezilungileyo?
Ukuba i-harmonic yesithathu inkulu kwaye i-harmonic yesibini incinci, mhlawumbi ngenxa yokuba umjikelo womsebenzi wesignali ngu-50%, kuba kule meko, isignali ayinayo i-harmonics.Ngeli xesha, kuyimfuneko ukuguqula umjikelo womsebenzi wesiginali.Ukongeza, ukuba umqondiso wewotshi awukho unidirectional, uthotho lwesiphelo somthombo lusetyenziswa ngokubanzi.Oku kucinezela imiboniso yesibini ngaphandle kokuchaphazela isantya somphetho wewotshi.Ixabiso elihambelanayo ekupheleni komthombo lingafumaneka ngokusebenzisa ifomula kumfanekiso ongezantsi.
39. Yintoni i-topology yocingo?
I-Topology, ezinye zikwabizwa ngokuba yi-routing order.Ngomyalelo wocingo lwe-multi-port edibeneyo yenethiwekhi.
40. Indlela yokulungelelanisa i-topology ye-wiring ukuphucula ukunyaniseka komqondiso?
Olu hlobo lwesalathiso somqondiso womnatha lunzima ngakumbi, kuba kwindlela enye, izibonakaliso zeendlela ezimbini, kunye neempawu zamanqanaba ahlukeneyo, i-topology ineempembelelo ezahlukeneyo, kwaye kunzima ukusho ukuba yeyiphi i-topology enenzuzo kumgangatho wesignali.Ngaphezu koko, xa usenza ukulinganisa kwangaphambili, yeyiphi i-topology ekufuneka isetyenziswe ifuna kakhulu kwiinjineli, kwaye ifuna ukuqonda imigaqo yesekethe, iintlobo zeempawu, kunye nobunzima bocingo.
41. Indlela yokunciphisa iingxaki ze-EMI ngokucwangcisa i-stackup?
Okokuqala, i-EMI kufuneka ithathelwe ingqalelo kwinkqubo, kwaye iPCB iyodwa ayinakuyisombulula ingxaki.Kwi-EMI, ndicinga ukuba ukupakisha kukubonelela ngeyona ndlela imfutshane yokubuya komqondiso, ukunciphisa indawo yokudibanisa, kunye nokucinezela ukuphazamiseka kwendlela yokwahlukana.Ukongeza, umaleko womhlaba kunye nomaleko wamandla udityaniswe ngokuqinileyo, kwaye ukwandiswa kukhulu ngokufanelekileyo kunomaleko wamandla, okulungele ukucinezela ukuphazamiseka kwendlela eqhelekileyo.
42. Kubekwe ntoni ubhedu?
Ngokuqhelekileyo, kukho izizathu ezininzi zokubeka ubhedu.
1. I-EMC.Kumhlaba omkhulu womhlaba okanye ubhedu lonikezelo lwamandla, luya kudlala indima yokukhusela, kwaye ezinye ezikhethekileyo, ezifana ne-PGND, ziya kudlala indima yokukhusela.
2. Iimfuno zenkqubo yePCB.Ngokuqhelekileyo, ukuze kuqinisekiswe umphumo we-electroplating okanye i-lamination ngaphandle kokuguqulwa, ubhedu lubekwe kwi-PCB layer kunye ne-wiring encinci.
3. Iimfuno zengqibelelo yomqondiso, zinika imiqondiso yedijithali ye-high-frequency indlela epheleleyo yokubuya, kunye nokunciphisa i-wiring yenethiwekhi ye-DC.Ngokuqinisekileyo, kukho nezizathu zokutshatyalaliswa kobushushu, ukufakwa kwesixhobo esikhethekileyo kufuna ukubeka ubhedu, njalo njalo.
43. Kwinkqubo, i-dsp kunye ne-pld zibandakanyiwe, zeziphi iingxaki ekufuneka ziqwalaselwe xa ufaka iintambo?
Jonga umlinganiselo wereyishini yomqondiso wakho ukuya kubude bocingo.Ukuba ukulibaziseka kwesignali kumgca wokuhambisa kuthelekiswa nexesha lokutshintsha komqondiso, ingxaki yengqibelelo yomqondiso kufuneka ithathelwe ingqalelo.Ukongezelela, kwii-DSP ezininzi, i-clock kunye nedatha yedatha ye-routing topology iya kuchaphazela umgangatho wesignali kunye nexesha, elifuna ukuqwalaselwa.
44. Ukongeza kwiprotel isixhobo socingo, ngaba kukho ezinye izixhobo ezilungileyo?
Ngokuphathelele izixhobo, ukongeza kwi-PROTEL, kukho izixhobo ezininzi zocingo, ezifana ne-MENTOR's WG2000, i-EN2000 series kunye ne-powerpcb, i-Cadence's allegro, i-zuken's cadstar, i-cr5000, njl., nganye inamandla ayo.
45. Yintoni “umzila womqondiso wokubuyela”?
Indlela yokubuya yomqondiso, oko kukuthi, ukubuyisela okwangoku.Xa isignali yedijithali enesantya esiphezulu ihanjiswa, umqondiso uphuma kumqhubi ecaleni komgca wothumelo we-PCB ukuya kumthwalo, kwaye ke umthwalo ubuyela ekupheleni komqhubi ecaleni komhlaba okanye unikezelo lwamandla ngeyona ndlela imfutshane.
Olu phawu lokubuya emhlabeni okanye unikezelo lwamandla lubizwa ngokuba yindlela yokubuya komqondiso.UGqr.Johnson wachaza kwincwadi yakhe ukuba ukuhanjiswa kwesignali ye-high-frequency ngokwenene yinkqubo yokutshaja i-dielectric capacitance sandwiched between the transmission line and the DC layer.Yintoni i-SI ehlalutya ngayo iipropati ze-electromagnetic zale ndawo ebiyelweyo kunye nokudibanisa phakathi kwazo.
46. Indlela yokuqhuba uhlalutyo lwe-SI kwizihlanganisi?
Kwinkcazo ye-IBIS3.2, kukho inkcazo yemodeli yokudibanisa.Ngokuqhelekileyo sebenzisa imodeli ye-EBD.Ukuba ibhodi ekhethekileyo, njenge-backplane, imodeli ye-SPICE iyadingeka.Unokusebenzisa isoftware yokulinganisa iibhodi ezininzi (HYPERLYNX okanye IS_multiboard).Xa ukwakhiwa kwenkqubo yeebhodi ezininzi, faka iiparitha zokusabalalisa iziqhagamshelo, ezifunyanwa ngokubanzi kwincwadana yokudibanisa.Ngokuqinisekileyo, le ndlela ayiyi kuchaneka ngokwaneleyo, kodwa ngokude nje ingaphakathi kuluhlu olwamkelekileyo.
47. Zeziphi iindlela zokuphelisa?
Ukupheliswa (isiphelo), ekwabizwa ngokuba kukutshatisa.Ngokubanzi, ngokwendawo ehambelanayo, yahlulwe yaba yisiphelo esisebenzayo sokuthelekisa kunye netheminali ehambelanayo.Phakathi kwazo, ukuthelekisana komthombo kungqamana nomdlalo wokuchasana, kwaye uthelekiso lwetheminali luhambelana ngokubanzi.Zininzi iindlela, ezibandakanya ukutsalwa kwe-resistor, ukutsalwa phantsi, ukuthelekisa i-Thevenin, ukuthelekisa i-AC, kunye ne-Schottky diode ehambelanayo.
48. Zeziphi izinto ezigqiba indlela yokuphelisa (ukutshatisa)?
Indlela yokudibanisa igqitywe ngokubanzi ngeempawu ze-BUFFER, iimeko ze-topology, iindidi zenqanaba kunye neendlela zokugweba, kunye nomjikelo womsebenzi womqondiso kunye nokusetyenziswa kwamandla enkqubo kufuneka kwakhona kuthathelwe ingqalelo.
49. Yeyiphi imigaqo yendlela yokuphelisa (ukutshatisa)?
Owona mba ubalulekileyo kwiisekethe zedijithali yingxaki yexesha.Injongo yokongeza ukuhambelana kukuphucula umgangatho wesignali kunye nokufumana isignali enokumiselwa ngexesha lokugweba.Kwinqanaba leempawu ezisebenzayo, umgangatho wesignali uzinzile phantsi kwesiseko sokuqinisekisa ukusekwa kunye nexesha lokubamba;ngenxa yeempawu ezibambezelekayo ezisebenzayo, phantsi kwesiseko sokuqinisekisa ukulibaziseka komqondiso we-monotonicity, isantya sokulibaziseka komqondiso sihlangabezana neemfuno.Kukho imathiriyeli yokumatanisa kwincwadi yemveliso ye-Mentor ICX.
Ukongeza, "Isantya esiphezulu seDijithali siyilo incwadi yesandla ye-blackmagic" inesahluko esinikezelwe kwi-terminal, esichaza indima yokudibanisa kwimfezeko yomqondiso ukusuka kumgaqo wamaza ombane, onokuthi usetyenziswe ukubhekisa.
50. Ndingasebenzisa imodeli ye-IBIS yesixhobo ukulinganisa umsebenzi wengqiqo wesixhobo?Ukuba akunjalo, ibhodi-level kunye ne-system-level-level simulations yesekethe yenziwa njani?
Iimodeli ze-IBIS ziyimodeli yenqanaba lokuziphatha kwaye ayinakusetyenziselwa ukulinganisa okusebenzayo.Ukulinganisa okusebenzayo, iimodeli ze-SPICE okanye ezinye iimodeli zomgangatho wolwakhiwo ziyafuneka.
51. Kwinkqubo apho idijithali kunye ne-analog zikhona, kukho iindlela ezimbini zokucubungula.Enye kukwahlula umhlaba wedijithali ukusuka kumhlaba we-analog.Amaso adityanisiwe, kodwa unikezelo lwamandla aluhlukaniswanga;enye kukuba unikezelo lwamandla analog kunye nonikezelo lwamandla edijithali bahlulwe kwaye baqhagamshelwe kwiFB, kwaye umhlaba ngumhlaba odibeneyo.Ndingathanda ukubuza uMnu. Li, ukuba ngaba isiphumo sezi ndlela zimbini ziyafana?
Kufuneka kuthiwe kuyafana nomgaqo.Ngenxa yokuba amandla kunye nomhlaba zilingana nemiqondiso ephezulu-frequency.
Injongo yokwahlula phakathi kwe-analog kunye ne-digital parts ku-anti-interference, ngokukodwa ukuphazamiseka kweesekethe zedijithali kwiisekethe ze-analog.Nangona kunjalo, ulwahlulo lunokubangela indlela yokubuyisela umqondiso ongaphelelanga, echaphazela umgangatho wesignali yesiginali yedijithali kunye nokuchaphazela umgangatho we-EMC wenkqubo.
Ngoko ke, kungakhathaliseki ukuba yiyiphi indiza eyahlulayo, kuxhomekeke ekubeni indlela yokubuyisela isignali yandisiwe kwaye ingakanani isignali yokubuya iphazamisa umqondiso oqhelekileyo wokusebenza.Ngoku kukho noyilo oluxubeneyo, kungakhathaliseki ukuba umbane kunye nomhlaba, xa ubeka, uhlukanise i-layout kunye ne-wiring ngokwecandelo ledijithali kunye nenxalenye ye-analog ukuphepha iimpawu ze-cross-regional.
52. Imigaqo yokhuseleko: Ziziphi iintsingiselo ezithile zeFCC kunye ne-EMC?
I-FCC: ikhomishini yonxibelelwano yomanyano yaseMelika
I-EMC: ukuhambelana kwe-electromagnetic ukuhambelana kwe-electromagnetic
I-FCC ngumbutho wemigangatho, i-EMC ngumgangatho.Kukho izizathu ezihambelanayo, imigangatho kunye neendlela zovavanyo zokubhengezwa kwemigangatho.
53. Yintoni umahluko?
Izibonakaliso ezihlukeneyo, ezinye zazo ezikwabizwa ngokuba yimiqondiso yokwahlukana, sebenzisa izibonakaliso ezimbini ezifanayo, ezichasene ne-polarity ukuhambisa ishaneli enye yedatha, kwaye uthembele kumahluko wenqanaba leempawu ezimbini zokugweba.Ukuze kuqinisekiswe ukuba izibonakaliso ezimbini zihambelana ngokupheleleyo, kufuneka zigcinwe ngokufana ngexesha locingo, kwaye ububanzi bomgca kunye nomgca wecala uhlala ungatshintshi.
54. Yintoni isoftware yokulinganisa iPCB?
Kukho iintlobo ezininzi zokulinganisa, isantya esiphezulu sedijithali yesekethe yedijithali uhlalutyo lokulinganisa ukulinganisa ukulinganisa (SI) isoftware esetyenziswa ngokuqhelekileyo yiicx, isignalivision, hyperlynx, XTK, spectraquest, njl njl. Abanye basebenzisa i-Hspice.
55. Isebenza njani isoftware yokulinganisa iPCB?
Kwiisekethe zedijithali ezikhawulezayo, ukwenzela ukuba kuphuculwe umgangatho wesignali kunye nokunciphisa ubunzima be-wiring, iibhodi ze-multi-layer ngokuqhelekileyo zisetyenziselwa ukwabela amandla akhethekileyo kunye neengqimba zomhlaba.
56. Indlela yokujongana ne-layout kunye ne-wiring ukuqinisekisa ukuzinza kweempawu ngaphezu kwe-50M
Isitshixo kwi-high-speed digital signal wiring kukunciphisa impembelelo yemigca yokuhambisa kumgangatho wesignali.Ngoko ke, ukucwangciswa kweempawu zesantya esiphezulu ngaphezu kwe-100M kufuna ukuba iimpawu zesignali zibe mfutshane ngokusemandleni.Kwiisekethe zedijithali, izibonakaliso zesantya esiphezulu zichazwe ngexesha lokulibaziseka kokunyuka kwesignali.Ngaphezu koko, iintlobo ezahlukeneyo zemiqondiso (ezifana ne-TTL, GTL, LVTTL) zineendlela ezahlukeneyo zokuqinisekisa umgangatho womqondiso.
57. Inxalenye yeRF yeyunithi yangaphandle, inxalenye yamaza omoya aphakathi, kunye nenxalenye yesekethe ye-low-frequency ebeka iliso kwiyunithi yangaphandle zihlala zifakwa kwiPCB enye.Zeziphi iimfuneko zemathiriyeli yePCB enjalo?Ukuthintela njani iRF, IF kunye neesekethe zamaza aphantsi ukuba ziphazamisane?
Uyilo lwesekethe yeHybrid yingxaki enkulu.Kunzima ukuba nesisombululo esigqibeleleyo.
Ngokubanzi, isekethe yerediyo yerediyo ibekwe phandle kwaye ifakwe iingcingo njengebhodi enye ezimeleyo kwinkqubo, kwaye kukho nomgodi okhethekileyo okhuselayo.Ngaphaya koko, isekethe yeRF iqhele ukuba cala-nye okanye inamacala amabini, kwaye isekethe ilula, konke oko kukunciphisa impembelelo kwiiparamitha zokusasaza kwisekethe yeRF kunye nokuphucula ukuhambelana kwenkqubo yeRF.
Xa kuthelekiswa ne-FR4 imathiriyeli jikelele, iibhodi ze-RF zesekethe zikholisa ukusebenzisa i-high-Q substrates.I-dielectric constant of this material incinci, i-capacitance esasazwayo yomgca wokuhambisa incinci, i-impedance iphezulu, kwaye ukulibaziseka kokuhanjiswa kwesignali kuncinci.Kuyilo lwesekethe ye-hybrid, nangona i-RF kunye neesekethe zedijithali zakhiwe kwi-PCB efanayo, zahlulahlulwe ngokubanzi kwindawo yesekethe ye-RF kunye nommandla wesekethe yedijithali, ezibekwe kwaye zitsalwe ngokwahlukeneyo.Sebenzisa ii-vias zomhlaba kunye neebhokisi zokukhusela phakathi kwazo.
58. Kwinxalenye yeRF, indawo ephakathi yamaza omoya kunye nenxalenye yesekethe ephantsi isasazwe kwiPCB enye, sisiphi isisombululo anaso umcebisi?
Isoftware yoyilo lwenkqubo yebhodi yeMentor, ukongeza kwimisebenzi yoyilo lwesekethe esisiseko, ikwanemodyuli yoyilo yeRF ezinikeleyo.Kwimodyuli yoyilo lwenkqubo ye-RF, imodeli yesixhobo esineparameter ibonelelwe, kunye nojongano lwe-bidirectional nohlalutyo lwesekethe yeRF kunye nezixhobo zokulinganisa ezifana neEESOFT zinikiwe;kwimodyuli yeRF LOKUBEKWA, umsebenzi wokuhlela ipateni osetyenziswa ngokukodwa kuyilo lwesekethe yeRF kunye nocingo lunikiwe, kwaye kukho kwakhona Ujongano lweendlela ezimbini zohlalutyo lwesekethe yeRF kunye nezixhobo zokulinganisa ezifana neEESOFT inokubuyisela umva-ileyibheli iziphumo zohlahlelo kunye Ukulinganisa umva kwidayagram yesikimu kunye nePCB.
Kwangaxeshanye, ukusebenzisa umsebenzi wolawulo loyilo lwesoftware yeMentor, ukuphinda kusetyenziswe uyilo, ukuyilwa koyilo, kunye noyilo olusebenzisanayo kunokufezekiswa ngokulula.Ukukhawulezisa kakhulu inkqubo yoyilo lwesekethe ye-hybrid.Ibhodi yefowuni ephathwayo luyilo lwesekethe oluxubeneyo oluqhelekileyo, kwaye abaninzi abavelisi boyilo lwefowuni ephathwayo basebenzisa iMentor kunye neeesoft zika-Angelon njengeqonga loyilo.
59. Yintoni isakhiwo semveliso yeMentor?
Izixhobo ze-PCB ze-Mentor 'zibandakanya i-WG (eyayifudula iyi-veribest) uthotho kunye nochungechunge lwe-Enterprise (ibhodi lebhodi).
60. I-Mentor's PCB uyila njani isoftware yokuxhasa i-BGA, i-PGA, i-COB kunye nezinye iipakethe?
I-Mentor's autoactive RE, ephuhliswe ekufumaneni i-Veribest, yindawo yokuqala yoshishino engenagridi, nayiphi na i-angle-router.Njengoko sonke sisazi, kuluhlu lwegridi yebhola, izixhobo ze-COB, i-gridless, kunye naziphi na ii-router ze-angle zisisitshixo sokusombulula ireyithi yendlela.Kwi-RE esebenzayo yamva nje, imisebenzi efana nokutyhala nge-vias, i-copper foil, i-REROUTE, njl.njl. yongezwe ukwenza kube lula ngakumbi ukufaka isicelo.Ukongeza, uxhasa ukuhamba ngesantya esiphezulu, kubandakanywa umzila wesignali kunye nokwahlukana kweendlela ezimbini kunye neemfuno zokulibaziseka kwexesha.
61. Ingaba iMentor's PCB uyila njani isoftwe yoyilo lwenkqubo yolwahlulo?
Emva kokuba i-software ye-Mentor ichaza iipropati zesibini esahlukileyo, izibini ezimbini ezihlukeneyo zinokuhanjiswa kunye, kunye nobubanzi bomgca, isithuba kunye nobude besibini esahlukileyo siqinisekisiwe ngokungqongqo.Zinokwahlulwa ngokuzenzekelayo xa zidibana nemiqobo, kwaye indlela yendlela inokukhethwa xa utshintsha iileya.
62. Kwibhodi ye-PCB ene-12-layer, kukho iileya ezintathu zonikezelo lwamandla 2.2v, 3.3v, 5v, kwaye nganye yezi zinto zintathu zombane zikumaleko omnye.Indlela yokujongana nocingo lomhlaba?
Ngokubanzi, unikezelo lwamandla oluthathu lucwangciswe ngokulandelelana kumgangatho wesithathu, ongcono kumgangatho weempawu.Ngenxa yokuba akunakwenzeka ukuba isignali iya kwahlulwa kwimigangatho yendiza.I-cross-segmentation yinto ebaluleke kakhulu echaphazela umgangatho wesignali engahoywa ngokubanzi yi-software yokulinganisa.Kwiinqwelomoya zamandla kunye neenqwelo-moya eziphantsi komhlaba, zilingana neempawu ze-high-frequency signals.Ngokwenza, ukongeza ekuqwalaseleni umgangatho wesignali, ukudibanisa kwendiza yamandla (usebenzisa i-plane yomhlaba ekufutshane ukuze kuncitshiswe i-AC impedance yendiza yamandla) kunye ne-stacking symmetry zizinto zonke ezifuna ukuqwalaselwa.
63. Ukukhangela njani ukuba iPCB iyahlangabezana neemfuno zenkqubo yoyilo xa ishiya umzi-mveliso?
Abavelisi abaninzi bePCB kufuneka badlule kuvavanyo lokuqhubeka kothungelwano lwamandla phambi kokuba inkqubo yePCB igqitywe ukuqinisekisa ukuba lonke uqhagamshelwano luchanekile.Kwangaxeshanye, ngakumbi nangakumbi abavelisi basebenzisa uvavanyo lwe-x-reyi ukujonga ezinye iimpazamo ngexesha le-etching okanye i-lamination.
Kwibhodi egqityiweyo emva kokucwangciswa kwe-patch, ukuhlolwa kovavanyo lwe-ICT kusetyenziswa ngokubanzi, nto leyo efuna ukongeza amanqaku ovavanyo lwe-ICT ngexesha loyilo lwePCB.Ukuba kukho ingxaki, isixhobo esikhethekileyo sokuhlola i-X-reyi sinokusetyenziselwa ukulawula ukuba ngaba impazamo ibangelwa kukusetyenzwa.
64. Ngaba “ukhuseleko lomatshini” lukhuselo lwebhokisi?
Ewe.I-casing kufuneka iqine kangangoko, sebenzisa izixhobo zokuqhuba ezingaphantsi okanye zingabikho, kwaye zibekwe phantsi kangangoko kunokwenzeka.
65. Ngaba kuyimfuneko ukuqwalasela ingxaki ye-esd yetshiphu ngokwayo xa ukhetha itshiphu?
Ingaba ibhodi ye-double-layer okanye ibhodi ye-multi-layer, indawo yomhlaba kufuneka inyuswe kangangoko kunokwenzeka.Xa ukhetha i-chip, iimpawu ze-ESD ze-chip ngokwayo kufuneka ziqwalaselwe.Ezi zikhankanyiwe ngokubanzi kwinkcazo ye-chip, kwaye nokusebenza kwe-chip efanayo kubakhiqizi abahlukeneyo kuya kwahluka.
Nika ingqalelo ngakumbi ukuyila kwaye uyiqwalasele ngokubanzi, kwaye ukusebenza kwebhodi yesekethe kuya kuqinisekiswa kwinqanaba elithile.Kodwa ingxaki ye-ESD isenokubonakala, ngoko ke ukhuseleko lombutho lubaluleke kakhulu ekukhuseleni i-ESD.
66. Xa usenza ibhodi ye-pcb, ukwenzela ukunciphisa ukuphazamiseka, ngaba ucingo lomhlaba kufuneka lufake ifom evaliweyo?
Xa usenza iibhodi ze-PCB, ngokuqhelekileyo, kuyimfuneko ukunciphisa indawo ye-loop ukunciphisa ukuphazamiseka.Xa ubeka ucingo lomhlaba, akufanele lubekwe kwifom evaliweyo, kodwa kwi-dendritic shape.Ummandla womhlaba.
67. Ukuba i-emulator isebenzisa umbane omnye kwaye ibhodi yePCb isebenzisa umbane omnye, ngaba imihlaba yamandla amabini kufuneka idityaniswe kunye?
Kuya kuba ngcono ukuba unikezelo lwamandla olwahlukileyo lunokusetyenziswa, kuba akulula ukubangela ukuphazamiseka phakathi kokunikezelwa kwamandla, kodwa uninzi lwezixhobo zineemfuno ezithile.Ekubeni i-emulator kunye nebhodi ye-PCB zisebenzisa izixhobo zombane ezimbini, andicingi ukuba kufuneka babelane nomhlaba ofanayo.
68. Isekethe yenziwe ngeebhodi ezininzi zepcb.Ngaba bafanele babelane ngomhlaba?
Isekethe ineePCB ezininzi, uninzi lwazo lufuna umhlaba oqhelekileyo, kuba akwenzeki ukusebenzisa izixhobo zombane ezininzi kwisekethe enye.Kodwa ukuba uneemeko ezithile, ungasebenzisa unikezelo lwamandla olwahlukileyo, ngokuqinisekileyo ukuphazamiseka kuya kuba kuncinci.
69. Yila imveliso ephathwa ngesandla kunye ne-LCD kunye neqokobhe lentsimbi.Xa uvavanya i-ESD, ayikwazi ukudlula uvavanyo lwe-ICE-1000-4-2, i-CONTACT inokudlula kuphela i-1100V, kwaye i-AIR inokudlula i-6000V.Kuvavanyo lokudibanisa i-ESD, i-horizontal inokudlula kuphela i-3000V, kwaye i-vertical ingadlula i-4000V.Ubuninzi be-CPU yi-33MHZ.Ngaba ikhona indlela yokuphumelela uvavanyo lwe-ESD?
Iimveliso eziphathwa ngesandla zizingxobo zesinyithi, ngoko ke iingxaki ze-ESD kufuneka zicace ngakumbi, kwaye iiLCDs zinokuba neziganeko ezimbi ngakumbi.Ukuba akukho ndlela yokutshintsha izinto zetsimbi ezikhoyo, kucetyiswa ukuba ungeze izinto ezichasene nombane ngaphakathi kwendlela yokuqinisa umhlaba wePCB, kwaye kwangaxeshanye ufumane indlela yokumisa iLCD.Kakade ke, indlela yokusebenza ixhomekeke kwimeko ethile.
70. Xa kuyilwa inkqubo equlathe i-DSP kunye ne-PLD, yeyiphi imiba ekufuneka ithathelwe ingqalelo i-ESD?
Ngokubhekiselele kwinkqubo ngokubanzi, iindawo ezithintana ngqo nomzimba womntu kufuneka ziqwalaselwe ngokukodwa, kwaye ukhuseleko olufanelekileyo kufuneka lwenziwe kwisekethe kunye nendlela.Ngokumalunga nokuba ingakanani impembelelo ye-ESD eya kuba nayo kwinkqubo, ixhomekeke kwiimeko ezahlukeneyo.
Ixesha lokuposa: Mar-19-2023