izindaba

Mhlawumbe ngemva komthetho ka-Ohm, umthetho wesibili odume kakhulu kweze-elekthronikhi umthetho kaMoore: Inani lama-transistors angenziwa kusekethe edidiyelwe liphindwe kabili njalo eminyakeni emibili noma ngaphezulu. Njengoba usayizi womzimba we-chip uhlala ucishe ufane, lokhu kusho ukuthi ama-transistors ngamanye azoba mancane ngokuhamba kwesikhathi. Sesiqalile ukulindela ukuthi isizukulwane esisha sama-chips anosayizi abancane besici sivele ngesivinini esijwayelekile, kodwa yini iphuzu lokwenza izinto zibe zincane? Ingabe okuncane kuhlala kusho okungcono?
Ekhulwini elidlule, ubunjiniyela be-elekthronikhi benze inqubekelaphambili enkulu. Ngawo-1920s, imisakazo ye-AM ethuthuke kakhulu yayihlanganisa amashubhu e-vacuum amaningana, ama-inductors amakhulu amaningana, ama-capacitor nama-resistors, inqwaba yamamitha ezintambo ezisetshenziswa njengezimpondo, kanye nesethi enkulu yamabhethri ukunika amandla yonke idivayisi. Namuhla, ungalalela izinsiza zokusakaza umculo ezingaphezu kweshumi nambili kudivayisi esephaketheni lakho, futhi ungenza okwengeziwe. Kodwa i-miniaturization ayikona nje ukuphatheka: kuyadingeka ngempela ukufeza ukusebenza esikulindele kumadivayisi wethu namuhla.
Inzuzo eyodwa esobala yezingxenye ezincane ukuthi zikuvumela ukuthi ufake ukusebenza okwengeziwe ngevolumu efanayo. Lokhu kubaluleke kakhulu kumasekhethi edijithali: izingxenye eziningi zisho ukuthi ungenza ukucubungula okwengeziwe ngesikhathi esifanayo. Isibonelo, ngokombono, inani lolwazi olucutshungulwe yi-64-bit processor liphindwe kasishiyagalombili kune-8-bit CPU esebenza ngewashi elifanayo. Kodwa futhi idinga izingxenye eziphindwe kasishiyagalombili: amarejista, ama-add, amabhasi, njll. zonke zinkulu ngokuphindwe kasishiyagalombili. Ngakho-ke udinga i-chip enkulu ngokuphindwe kasishiyagalombili, noma udinga i-transistor encanyana ngokuphindwe kasishiyagalombili.
Okufanayo kuyiqiniso kuma-memory chips: Ngokwenza ama-transistors amancane, unendawo yokubeka eyengeziwe ngevolumu efanayo. Amaphikseli kuzibonisi eziningi namuhla enziwe ngama-transistors efilimu azacile, ngakho-ke kunengqondo ukuwehlisa futhi uzuze izinqumo eziphezulu. Kodwa-ke, i-transistor encane, ingcono, futhi kunesinye isizathu esibalulekile: ukusebenza kwabo kuba ngcono kakhulu. Kodwa kungani ngempela?
Noma nini lapho wenza i-transistor, izohlinzeka ngezingxenye ezengeziwe mahhala. Itheminali ngayinye ine-resistor ochungechungeni. Noma iyiphi into ephethe i-current iphinde ibe ne-self-inductance. Ekugcineni, kukhona i-capacitance phakathi kwanoma yimaphi amakhondaktha amabili abhekene. Yonke le miphumela idla amandla futhi yehlise isivinini se-transistor. Amandla e-Parasitic ayinkinga kakhulu: ama-transistors adinga ukushajwa futhi akhululwe isikhathi ngasinye lapho evuliwe noma ecishwa, okudinga isikhathi namandla kusuka kumandla kagesi.
I-capacitance phakathi kwama-conductor amabili iwumsebenzi wosayizi wabo womzimba: usayizi omncane usho amandla amancane. Futhi ngenxa yokuthi ama-capacitor amancane asho isivinini esikhulu namandla aphansi, ama-transistors amancane angasebenza ngamaza ewashi aphezulu futhi akhiphe ukushisa okuncane ngokwenza kanjalo.
Njengoba unciphisa usayizi wama-transistors, amandla akuwona ukuphela komphumela oguqukayo: kunemiphumela eminingi eyinqaba ye-quantum mechanical engabonakali kumadivayisi amakhulu. Kodwa-ke, ngokujwayelekile, ukwenza ama-transistors abe mancane kuzowenza asheshe. Kodwa imikhiqizo ye-elekthronikhi ingaphezu nje kwama-transistors. Uma wehlisa ezinye izingxenye, zisebenza kanjani?
Ngokuvamile, izingxenye ze-passive ezifana nama-resistors, ama-capacitor, nama-inductors ngeke zibe ngcono uma ziba zincane: ngezindlela eziningi, zizoba zimbi kakhulu. Ngakho-ke, ukwenziwa kancane kwalezi zingxenye ngokuyinhloko ukukwazi ukuzicindezela zibe ivolumu encane, ngaleyo ndlela konga isikhala se-PCB.
Usayizi we-resistor ungancishiswa ngaphandle kokubangela ukulahlekelwa okukhulu. Ukumelana nocezu lwento kunikezwa ngokuthi, lapho u-l engubude, u-A uyindawo ephambanayo, futhi u-ρ uwukumelana kwezinto. Ungamane unciphise ubude nesigaba esiphambanayo, futhi ugcine une-resistor encane ngokomzimba, kodwa usenokumelana okufanayo. Okuwukuphela kokubi ukuthi lapho kuchithwa amandla afanayo, izinto eziphikisayo ezincane ezingokwenyama zizokhiqiza ukushisa okungaphezulu kunezinqamuli ezinkulu. Ngakho-ke, ama-resistors amancane angasetshenziswa kuphela kumasekethe anamandla aphansi. Leli thebula libonisa ukuthi isilinganiso samandla esiphezulu se-SMD resistors sehla kanjani njengoba usayizi wabo uncipha.
Namuhla, i-resistor encane kakhulu ongayithenga ingusayizi we-metric 03015 (0.3 mm x 0.15 mm). Amandla azo alinganiselwe angama-20 mW kuphela futhi asetshenziselwa amasekhethi achitha amandla amancane kakhulu futhi anosayizi olinganiselwe kakhulu. Iphakheji elincane le-metric 0201 (0.2 mm x 0.1 mm) likhishiwe, kodwa alikakafakwa ekukhiqizeni. Kodwa noma ngabe zivela kukhathalogi yomkhiqizi, ungalindeli ukuthi zikhona yonke indawo: amarobhothi amaningi akhethayo nendawo awanembile ngokwanele ukuwaphatha, ngakho-ke angase abe yimikhiqizo ye-niche.
Ama-Capacitor nawo angehliswa, kodwa lokhu kuzonciphisa amandla awo. Ifomula yokubala i-capacitance ye-shunt capacitor iwukuthi, lapho u-A eyindawo yebhodi, d yibanga eliphakathi kwabo, futhi ε yi-dielectric constant (impahla yezinto eziphakathi nendawo). Uma i-capacitor (ngokuyisisekelo idivayisi eyisicaba) i-miniaturized, indawo kufanele incishiswe, ngaleyo ndlela inciphise i-capacitance. Uma usafuna ukupakisha i-nafara eningi ngevolumu encane, okuwukuphela kwenketho ukupakisha izendlalelo ezimbalwa ndawonye. Ngenxa yentuthuko yezinto zokwakha kanye nokukhiqiza, okuphinde kwenze amafilimu amancane (amancane d) kanye nama-dielectrics akhethekile (ano-ε amakhulu) okungenzeka, ubukhulu bama-capacitor bunciphe kakhulu emashumini ambalwa eminyaka adlule.
I-capacitor encane kunazo zonke etholakalayo namuhla ikuphakheji ye-metric 0201: 0.25 mm x 0.125 mm kuphela. Amandla abo akhawulelwe ku-100 nF namanje ewusizo, futhi i-voltage yokusebenza ephezulu ingu-6.3 V. Futhi, lawa maphakheji mancane kakhulu futhi adinga imishini ethuthukisiwe ukuwaphatha, anciphisa ukutholwa kwawo okusabalele.
Kuma-inductors, indaba inobuqili. I-inductance yekhoyili eqondile inikezwa, lapho u-N eyinombolo yokujika, A indawo enqamulayo yekhoyili, l ubude bayo, futhi u-μ yizinto ezingaguquki (permeability). Uma zonke izilinganiso zincishiswa ngesigamu, i-inductance izophinde yehliswe ngesigamu. Kodwa-ke, ukuphikiswa kocingo kuhlala kufana: lokhu kungenxa yokuthi ubude ne-cross-section yocingo kuncipha kube ingxenye yesine yenani layo lokuqala. Lokhu kusho ukuthi ugcina usunokumelana okufanayo kuhhafu we-inductance, ngakho-ke unciphisa izinga (Q) factor yekhoyili.
I-inductor encane etholakalayo etholakalayo kwezohwebo isebenzisa usayizi weyintshi 01005 (0.4 mm x 0.2 mm). Lawa aphakeme njengo-56 nH futhi anokumelana nama-ohm ambalwa. Ama-inductors ephaketheni le-ultra-small metric 0201 akhululwa ngo-2014, kodwa ngokusobala awakaze athulwe emakethe.
Ukulinganiselwa ngokomzimba kwama-inductors kuye kwaxazululwa ngokusebenzisa into ebizwa ngokuthi i-dynamic inductance, engabonwa kumakhoyili enziwe nge-graphene. Kodwa noma kunjalo, uma ingakhiqizwa ngendlela ekwazi ukuhweba, ingase yenyuke ngo-50%. Okokugcina, ikhoyili ayikwazi ukwenziwa i-miniaturized kahle. Kodwa-ke, uma isifunda sakho sisebenza kumafrikhwensi aphezulu, lokhu akuyona inkinga. Uma isignali yakho ikububanzi be-GHz, amakhoyili ambalwa e-nH ngokuvamile anele.
Lokhu kusiletha kwenye into eyenziwe yaba mincane eminyakeni eyikhulu edlule kodwa ungase ungaqapheli ngokushesha: ubude begagasi esibusebenzisela ukuxhumana. Ukusakazwa komsakazo kwasekuqaleni kwakusebenzisa i-AM yegagasi elimaphakathi cishe engu-1 MHz enobude obungamamitha angama-300. Ibhendi yefrikhwensi ye-FM egxile ku-100 MHz noma amamitha angu-3 yaduma ngeminyaka yawo-1960, futhi namuhla sisebenzisa kakhulu ukuxhumana kwe-4G eduze no-1 noma 2 GHz (cishe ama-20 cm). Amafrikhwensi aphezulu asho umthamo wokudlulisa ulwazi olwengeziwe. Kungenxa ye-miniaturization eyenza sibe nemisakazo eshibhile, ethembekile futhi ewonga amandla asebenza kulawa maza.
Amaza amaza anciphayo angashwabanisa izimpondo ngoba usayizi wazo uhlobene ngokuqondile nemvamisa ezidinga ukuyidlulisa noma yokwamukela. Omakhalekhukhwini banamuhla abawadingi ama-antenna amade aphumela ngaphandle, ngenxa yokuxhumana kwabo okuzinikele kumafrikhwensi e-GHz, okuthi uthi ludinga ubude obuyisentimitha elilodwa kuphela. Kungakho omakhalekhukhwini abaningi abasaqukethe izamukeli ze-FM bedinga ukuthi uxhume izindlebe ngaphambi kokusetshenziswa: umsakazo udinga ukusebenzisa intambo ye-earphone njengothi ukuze uthole amandla esiginali anele kulawo maza amade ayimitha elilodwa.
Ngokuqondene namasekhethi axhunywe kuma-antenna ethu amancane, lapho emancane, aba lula ukuwenza. Lokhu akukona nje ukuthi ama-transistors aseshesha, kodwa futhi ngoba imiphumela yolayini wokudlulisela ayiseyona inkinga. Ngamafuphi, lapho ubude bocingo budlula ingxenye eyodwa kweshumi ye-wavelength, udinga ukucabangela ukushintshwa kwesigaba ngobude baso lapho uklama isifunda. Ku-2.4 GHz, lokhu kusho ukuthi isentimitha elilodwa kuphela locingo elithinte umjikelezo wakho; uma uthengisa izingxenye ezihlukene ndawonye, ​​​​kubuhlungu bekhanda, kodwa uma ubeka isifunda ngamamilimitha ayisikwele ambalwa, akuyona inkinga.
Ukubikezela ukushabalala koMthetho kaMoore, noma ukukhombisa ukuthi lezi zibikezelo azilungile kaningi, sekuyindikimba ephindaphindayo kubuntatheli besayensi nobuchwepheshe. Iqiniso liwukuthi i-Intel, i-Samsung, ne-TSMC, izimbangi ezintathu ezisahamba phambili emdlalweni, ziyaqhubeka nokucindezela izici eziningi nge-micrometer yesikwele, futhi zihlela ukwethula izizukulwane ezimbalwa zama-chips athuthukisiwe esikhathini esizayo. Ngisho noma inqubekelaphambili abayenzile esinyathelweni ngasinye ingase ingabi nkulu njengamashumi amabili eminyaka edlule, ukwakhiwa kwe-miniaturization kwama-transistors kuyaqhubeka.
Kodwa-ke, ezingxenyeni ezihlukene, kubonakala sengathi sifinyelele umkhawulo ongokwemvelo: ukuzenza zibe zincane akuthuthukisi ukusebenza kwazo, futhi izingxenye ezincane kakhulu ezitholakalayo njengamanje zincane kunezimo eziningi zokusetshenziswa ezidingekayo. Kubonakala sengathi awukho uMthetho kaMoore wamadivayisi ahlukene, kodwa uma kukhona uMthetho kaMoore, singathanda ukubona ukuthi umuntu oyedwa angayiphusha kangakanani inselelo yokudayiswa kwe-SMD.
Bengilokhu ngifuna ukuthatha isithombe se-PTH resistor engangiyisebenzisa ngawo-1970s, futhi ngifake i-SMD resistor kuso, njengoba nje ngishintshashintsha / ngiphuma manje. Umgomo wami uwukwenza abafowethu nodadewethu (akekho kubo oyimikhiqizo ye-elekthronikhi) ukuthi lungakanani ushintsho, okuhlanganisa ngakwazi ngisho nokubona izingxenye zomsebenzi wami, (njengoba amehlo ami aya ngokuba mabi kakhulu, izandla zami ziba zimbi Ngokuthuthumela).
Ngithanda ukusho, ingabe sindawonye noma cha. Ngiyakuzonda ngempela ukuthi “thuthuka, ube ngcono.” Kwesinye isikhathi isakhiwo sakho sisebenza kahle, kodwa awusakwazi ukuthola izingxenye. Kuyini lokho? . Umqondo omuhle umqondo omuhle, futhi kungcono ukuwugcina njengoba unjalo, kunokuba uwuthuthukise ngaphandle kwesizathu. Gantt
"Iqiniso liwukuthi izinkampani ezintathu ze-Intel, i-Samsung ne-TSMC zisaqhudelana phambili kulo mdlalo, zilokhu zicindezela izici eziningi nge-micrometer ngayinye yesikwele,"
Izingxenye zikagesi zinkulu futhi ziyabiza. Ngo-1971, umkhaya ovamile wawunemisakazo embalwa kuphela, isitiriyo ne-TV. Ngo-1976, amakhompyutha, izibali, amawashi edijithali namawashi ayesephumile, ayemancane futhi engabizi kubathengi.
Enye i-miniaturization ivela kumklamo. Ama-amplifiers okusebenza avumela ukusetshenziswa kwama-gyrators, angashintsha ama-inductors amakhulu kwezinye izimo. Izihlungi ezisebenzayo nazo zisusa ama-inductors.
Izingxenye ezinkulu zikhuthaza ezinye izinto: ukuncishiswa kwesekethe, okungukuthi, ukuzama ukusebenzisa izingxenye ezimbalwa ukwenza umsebenzi wesifunda. Namuhla, asinandaba kangako. Udinga okuthile ukuze uhlehlise isignali? Thatha i-amplifier yokusebenza. Ingabe udinga umshini wombuso? Thatha impu. njll. Izingxenye namuhla zincane ngempela, kodwa empeleni ziningi izingxenye ngaphakathi. Ngakho-ke ngokuyisisekelo usayizi wakho wesifunda uyakhuphuka futhi ukusetshenziswa kwamandla kuyanda. I-transistor esetshenziselwa ukuguqula isignali isebenzisa amandla amancane ukuze ifeze umsebenzi ofanayo kune-amplifier yokusebenza. Kepha futhi, i-miniaturization izonakekela ukusetshenziswa kwamandla. Ukuthi nje ukuqamba okusha kuhambe ngenye indlela.
Uphuthelwe ngempela ezinye zezinzuzo/izizathu ezinkulu zosayizi oncishisiwe: izimuncagazi ezincishisiwe zephakeji kanye nokuphathwa kwamandla okukhulisiwe (okubonakala kungenangqondo).
Ngokombono ongokoqobo, uma usayizi wesici ufinyelela cishe ku-0.25u, uzofinyelela izinga le-GHz, ngaleso sikhathi iphakheji elikhulu le-SOP liqala ukukhiqiza umphumela omkhulu kakhulu*. Izintambo ezinde ezibophayo kanye nalabo abaholayo ekugcineni bazokubulala.
Kuleli qophelo, amaphakheji e-QFN/BGA athuthuke kakhulu ngokuya ngokusebenza. Ngaphezu kwalokho, uma ukhweza iphakheji isicaba ngale ndlela, ugcina usunokusebenza *okubalulekile* okushisayo namaphedi avuliwe.
Ngaphezu kwalokho, i-Intel, i-Samsung, ne-TSMC izodlala indima ebalulekile, kodwa i-ASML ingase ibaluleke kakhulu kulolu hlu. Yebo, lokhu kungase kungasebenzi ezwini lokwenziwa...
Akukhona nje ngokunciphisa izindleko ze-silicon ngokusebenzisa ama-node enqubo yesizukulwane esilandelayo. Ezinye izinto, njengezikhwama. Amaphakheji amancane adinga izinto ezincane kanye ne-wcsp noma ngaphansi. Amaphakheji amancane, ama-PCB amancane noma amamojula, njll.
Ngivame ukubona imikhiqizo ethile yekhathalogi, lapho okuwukuphela kwesici sokushayela siwukunciphisa izindleko. Usayizi we-MHz/inkumbulo uyafana, umsebenzi we-SOC nokuhlelwa kwephini kuyafana. Singase sisebenzise ubuchwepheshe obusha ukuze sinciphise ukusetshenziswa kwamandla (imvamisa lokhu akumahhala, ngakho kufanele kube nezinzuzo ezithile ezincintisanayo amakhasimende azinakayo)
Enye yezinzuzo zezingxenye ezinkulu yi-anti-radiation material. Ama-transistors amancane athinteka kakhulu emiphumeleni yemisebe ye-cosmic, kulesi simo esibalulekile. Isibonelo, emkhathini ngisho nasezindaweni zokubuka eziphakeme.
Angisibonanga isizathu esikhulu sokwenyuka kwesivinini. Ijubane lesignali licishe libe ngamayintshi angu-8 nanosecond ngayinye. Ngakho-ke ngokunciphisa nje usayizi, ama-chips asheshayo angenzeka.
Ungase ufune ukuhlola eyakho imathematika ngokubala umehluko ekubambezelekeni kokusabalalisa ngenxa yezinguquko zokupakisha nemijikelezo encishisiwe (1/imvamisa). Lokho kusho ukunciphisa ukubambezeleka/inkathi yamaqembu. Uzothola ukuthi akubonisi ngisho njengento ehlanganisayo.
Into eyodwa engifuna ukuyengeza ukuthi ama-IC amaningi, ikakhulukazi amadizayini amadala nama-analog chips, awehliswanga ngokweqiniso, okungenani ngaphakathi. Ngenxa yentuthuko ekukhiqizeni okuzenzakalelayo, amaphakheji abe mancane, kodwa lokho kungenxa yokuthi amaphakheji e-DIP ngokuvamile anendawo eningi esele ngaphakathi, hhayi ngoba ama-transistors njll.
Ngokungeziwe enkingeni yokwenza irobhothi linembe ngokwanele ukuthi likwazi ukuphatha izingxenye ezincane ezinhlelweni zokukhetha nendawo enesivinini esikhulu, enye inkinga ukushisela izingxenye ezincane ngokuthembekile. Ikakhulukazi uma usadinga izingxenye ezinkulu ngenxa yezidingo zamandla/umthamo. Ukusebenzisa unamathisele okhethekile we-solder, izifanekiso ezikhethekile zokunamathisela isinyathelo solder (sebenzisa inani elincane lokunamathisela i-solder lapho kudingeka khona, kodwa namanje unikeze unamathisele okwanele we-solder wezingxenye ezinkulu) waqala ukubiza kakhulu. Ngakho-ke ngicabanga ukuthi kunethafa, futhi ukwenza kancane kancane ezingeni lebhodi lesifunda kuyindlela ebizayo futhi engenzeka. Kuleli qophelo, ungase wenze ukuhlanganiswa okwengeziwe ezingeni le-silicon wafer futhi wenze lula inani lezingxenye ezihlukene libe ubuncane obuphelele.
Uzobona lokhu ocingweni lwakho. Cishe ngo-1995, ngathenga omakhalekhukhwini bokuqala ekuthengisweni kwegaraji ngamadola ambalwa lilinye. Ama-IC amaningi anembobo. I-CPU ebonakalayo ne-NE570 compander, i-IC enkulu esebenziseka kabusha.
Ngabe sengigcina nginamafoni aphathwayo abuyekeziwe. Kunezingxenye ezimbalwa kakhulu futhi cishe akukho okujwayelekile. Ngenani elincane lama-IC, akuwona kuphela ukuminyana okuphakeme, kodwa futhi nomklamo omusha (bona i-SDR) uyamukelwa, oqeda iningi lezingxenye ezihlukene ebezidingeka ngaphambilini.
> (Faka inani elincane lokunamathisela i-solder lapho kudingeka khona, kodwa unikeze unamathisele we-solder owanele wezingxenye ezinkulu)
Sawubona, ngicabange isifanekiso se-"3D/Wave" sokuxazulula le nkinga: sizacile lapho kunezingxenye ezincane kakhulu, futhi sibe sishubile lapho isifunda samandla sikhona.
Kulezi zinsuku, izingxenye ze-SMT zincane kakhulu, ungasebenzisa izingxenye zangempela ezihlukene (hhayi i-74xx nezinye izibi) ukuze udizayine eyakho i-CPU futhi uyiphrinte ku-PCB. Yifafaze nge-LED, ungayibona isebenza ngesikhathi sangempela.
Phakathi neminyaka edlule, ngiyakwazisa ngempela ukuthuthukiswa okusheshayo kwezingxenye eziyinkimbinkimbi nezincane. Banikeza inqubekelaphambili enkulu, kodwa ngesikhathi esifanayo bengeza izinga elisha lokuyinkimbinkimbi enqubweni ephindaphindayo ye-prototyping.
Ukulungiswa kanye nesivinini sokulingisa samasekhethi e-analog sishesha kakhulu kunalokho okwenzayo elabhorethri. Njengoba imvamisa yamasekhethi edijithali ikhuphuka, i-PCB iba yingxenye yomhlangano. Isibonelo, imiphumela yomugqa wokudlulisela, ukubambezeleka kokusabalalisa. I-Prototyping yanoma ibuphi ubuchwepheshe obusezingeni eliphezulu busetshenziswa kangcono ekuqedeni umklamo ngendlela efanele, kunokuba kwenziwe izinguquko elabhorethri.
Ngokuqondene nezinto zokuzilibazisa, ukuhlola. Amabhodi esifunda namamojula ayisixazululo sezingxenye ezinciphayo kanye namamojula okuhlola ngaphambilini.
Lokhu kungase kwenze izinto zilahlekelwe “ubumnandi”, kodwa ngicabanga ukuthi ukwenza iphrojekthi yakho isebenze okokuqala kungase kube nenjongo ngenxa yomsebenzi noma izinto zokuzilibazisa.
Bengilokhu ngiguqula imiklamo ethile isuka ku- through-hole iye ku-SMD. Yenza imikhiqizo eshibhile, kodwa akujabulisi ukwakha ama-prototypes ngesandla. Iphutha elilodwa elincane: "indawo ehambisanayo" kufanele ifundwe njenge "parallel plate".
Cha. Ngemva kokuba uhlelo luphumelele, abavubukuli basazodideka ngalokho abakutholile. Kwazi bani, mhlawumbe ngekhulu lama-23, iPlanetary Alliance izosebenzisa uhlelo olusha…
Angikwazanga ukuvuma okwengeziwe. Ungakanani usayizi we-0603? Yebo, ukugcina u-0603 njengosayizi wombuso kanye “nokushayela” usayizi wemethrikhi 0603 0604 (noma 0602) akunzima kangako, noma ngabe kungalungile ngokobuchwepheshe (okungukuthi: usayizi wokufanisa wangempela-hhayi ngaleyo ndlela) noma kunjalo. Iqinile), kodwa okungenani wonke umuntu uzokwazi ukuthi iyiphi ubuchwepheshe okhuluma ngabo (imethrikhi/imperial)!
"Ngokuvamile, izakhi zokungenzi lutho ezifana neziphikisayo, ama-capacitor, nama-inductors ngeke zibe ngcono uma uzenza zibe zincane."