Ngaba uyayazi isekethe yomqhubi we-MOSFET?

Isekethe yomqhubi we-MOSFET yinxalenye ebalulekileyo yombane we-elektroniki kunye noyilo lwesekethe, enoxanduva lokubonelela ngesakhono sokuqhuba ngokwaneleyo ukuqinisekisa ukuba i-MOSFET inokusebenza ngokufanelekileyo nangokuthembekileyo. Oku kulandelayo luhlalutyo oluneenkcukacha lweesekethe zabaqhubi be-MOSFET:

I. Indima yesekethe yokuqhuba

Nika umthamo owaneleyo wokuqhuba:Ekubeni i-drive signal idla ngokunikezelwa kumlawuli (umzekelo, i-DSP, i-microcontroller), i-voltage ye-drive kunye ne-current isenokungonelanga ukuyivula ngqo i-MOSFET, ngoko ke isekethe yokuqhuba iyafuneka ukuze ihambelane nesakhono sokuqhuba.

Qinisekisa iimeko ezifanelekileyo zokutshintsha:Isekethe yomqhubi kufuneka iqinisekise ukuba ii-MOSFETs azikhawulezi kakhulu kwaye azicothi kakhulu ngexesha lokutshintsha ukuthintela iingxaki ze-EMI kunye nelahleko yokutshintsha ngokugqithisileyo.

Qinisekisa ukuthembeka kwesixhobo:Ngenxa yobukho beeparameters zeparasitic isixhobo sokutshintsha, i-voltage-current spikes inokuveliswa ngexesha lokuqhuba okanye ukucima, kwaye isiphaluka somqhubi kufuneka sicinezele ezi spikes ukukhusela isiphaluka kunye nesixhobo.

II. Iintlobo zeesekethe zokuqhuba

Umqhubi ongekho yedwa

Qhuba ngokuthe ngqo:Eyona ndlela ilula yokuqhuba i-MOSFET kukudibanisa isiginali yedrive ngqo kwisango le-MOSFET. Le ndlela ifanelekile kwizihlandlo apho amandla okuqhuba anele kwaye imfuno yodwa ayiphezulu.

ISekethe yeBootstrap:Ukusebenzisa umgaqo wokuba amandla ombane we-capacitor akanakuguqulwa ngequbuliso, amandla ombane aphakanyiswa ngokuzenzekelayo xa i-MOSFET itshintsha isimo sayo sokutshintsha, ngaloo ndlela iqhuba i-MOSFET ene-voltage ephezulu. umqhubi IC, ezifana neesekethe BUCK.

Umqhubi Oyedwa

Ukwahlukaniswa kwe-Optocoupler:Ukwahlukaniswa komqondiso we-drive ukusuka kwisekethe eyintloko kufezekiswa ngokusebenzisa i-optocouplers. I-Optocoupler ineenzuzo zokuzihlukanisa kombane kunye nobuchule obunamandla bokuchasana nokuphazamiseka, kodwa impendulo ye-frequency inokunciphisa, kwaye ubomi kunye nokuthembeka kunokuncitshiswa phantsi kweemeko ezinzima.

Ukwahlulwa kweTransformer:Ukusetyenziswa kwee-transformers ukufezekisa ukuhlukaniswa kwesignali ye-drive ukusuka kwisiphaluka esikhulu. Ukwahlukaniswa kwe-transformer kunezibonelelo zokuphendula okuhle kwe-high-frequency, i-voltage ephezulu yokuzimela, njl.

Okwesithathu, uyilo lwamanqaku esekethe zokuqhuba

Umbane wokuqhuba:Kufuneka kuqinisekiswe ukuba amandla ombane okuqhuba angaphezulu kombane we-MOSFET ukuqinisekisa ukuba i-MOSFET inokuqhuba ngokuthembekileyo. Kwangaxeshanye, i-voltage yokuqhuba akufuneki ibe phezulu kakhulu ukunqanda ukonakalisa iMOSFET.

Qhuba ngoku:Nangona ii-MOSFET zizixhobo eziqhutywa ngamandla ombane kwaye azifuni kuqhuba ngokuqhubekayo, isantya esiphezulu kufuneka siqinisekiswe ukuze kuqinisekiswe isantya esithile sokutshintsha. Ngoko ke, isekethe yomqhubi kufuneka ikwazi ukubonelela ngokufanelekileyo i-peak current.

Qhuba isixhasi:I-resistor yokuqhuba isetyenziselwa ukulawula isantya sokutshintsha kunye nokucinezela i-spikes yangoku. Ukukhethwa kwexabiso lokumelana kufuneka kusekelwe kwisekethe ethile kunye neempawu ze-MOSFET. Ngokuqhelekileyo, ixabiso lokumelana akufanele libe likhulu okanye lincinci kakhulu ukuphepha ukuchaphazela umphumo wokuqhuba kunye nokusebenza kwesekethe.

Uyilo lwePCB:Ngethuba lokuhlelwa kwe-PCB, ubude bokulungelelaniswa phakathi kwesekethe yomqhubi kunye nesango le-MOSFET kufuneka lifinyezwe kangangoko kunokwenzeka, kwaye ububanzi bokulungelelaniswa kufuneka bunyuswe ukunciphisa impembelelo ye-parasitic inductance kunye nokuchasana kwisiphumo sokuqhuba. Kwangaxeshanye, amacandelo aphambili anjengezixhasi zokuqhuba kufuneka abekwe kufutshane nesango le-MOSFET.

IV. Imizekelo yezicelo

Iisekethe zomqhubi we-MOSFET zisetyenziswa ngokubanzi kwiintlobo ngeentlobo zezixhobo zombane zamandla kunye neesekethe, ezinjengokutshintsha izixhobo zombane, ii-inverters, kunye neemoto zokuqhuba. Kwezi zicelo, ukuyila kunye nokulungiswa kweesekethe zomqhubi zibalulekile ekuphuculeni ukusebenza kunye nokuthembeka kwezixhobo.

Isishwankathelo, i-MOSFET yokuqhuba isekethe yinxalenye eyimfuneko yombane we-elektroniki kunye noyilo lwesekethe. Ngokuyila ngokufanelekileyo isekethe yomqhubi, inokuqinisekisa ukuba i-MOSFET isebenza ngokwesiqhelo nangokuthembekileyo, ngaloo ndlela iphucula ukusebenza kunye nokuthembeka kwesekethe iphela.