Ungakhetha kanjani i-MOSFET?

Kunezinhlobo ezimbili zama-MOSFET, i-N-channel kanye ne-P-channel. Ezinhlelweni zamandla,Ama-MOSFETkungabhekwa njengokushintshwa kukagesi. Ukushintshwa kwe-N-channel MOSFET kuqhuba lapho i-voltage evumayo yengezwa phakathi kwesango nomthombo. Ngenkathi uqhuba, i-current ingageleza ngokushintsha isuka ku-drain iye emthonjeni. Kukhona ukumelana kwangaphakathi phakathi komsele kanye nomthombo obizwa nge-on-resistance RDS(ON).

 

I-MOSFET njengengxenye eyisisekelo yesistimu kagesi, i-Guanhua Weiye ikutshela ukuthi ungenza kanjani ukukhetha okufanele ngokuya ngemingcele?

I. Ukukhethwa Kwesiteshi

Isinyathelo sokuqala ekukhetheni idivayisi efanele yomklamo wakho ukunquma ukuthi usebenzise i-N-channel noma i-P-channel MOSFET. ezinhlelweni zamandla, i-MOSFET iyamiswa futhi umthwalo uxhunywe ku-voltage ye-trunk lapho i-MOSFET yenza iswishi eseceleni ene-voltage ephansi. Ama-MOSFET wesiteshi se-N kufanele asetshenziswe ekushintsheni ohlangothini lwe-voltage ephansi ngenxa yokucatshangelwa kwamandla kagesi adingekayo ukuze uvale noma uvule idivayisi. Ukushintsha uhlangothi lwe-voltage ephezulu kufanele kusetshenziswe uma i-MOSFET ixhunywe ebhasini nasekuxhumekeni komhlaba.

 

II. Ukukhetha Voltage futhi Yamanje

Lapho i-voltage elinganiselwe iphezulu, izindleko zedivayisi ziphezulu. Ngokusho kokuhlangenwe nakho okungokoqobo, i-voltage elinganiselwe kufanele ibe nkulu kune-trunk voltage noma ibhasi. Kulapho kuphela lapho inganikeza khona ukuvikeleka okwanele ekuhlulekeni kwe-MOSFET. Lapho ukhetha i-MOSFET, umthamo omkhulu we-voltage ukusuka ku-drain ukuya emthonjeni udinga ukunqunywa.

Kumodi yokuqhuba eqhubekayo, iI-MOSFETisesimweni esingaguquki, lapho i-current idlula ngokuqhubekayo ocingweni. Ama-pulse spikes yilapho kukhona ama-surges amakhulu (noma ama-peak currents) ageleza kudivayisi. Uma umthamo wamanje usunqunyiwe ngaphansi kwalezi zimo, vele ukhethe idivayisi engakwazi ukumelana nomthamo omkhulu wamanje.

 

Okwesithathu, ukulahleka kokuqhuba

Ngenxa yokuthi ukumelana nokushisa kuyahlukahluka ngokwezinga lokushisa, ukulahlekelwa kwamandla kuzohluka ngokulinganayo. Ekwakheni okuphathekayo, ukusetshenziswa kwamandla kagesi aphansi kuvame kakhulu, kanti ekwakhiweni kwezimboni, amandla kagesi aphezulu angasetshenziswa.

 

Izidingo Zokushisa Zesistimu

Mayelana nezidingo zokupholisa isistimu, i-Crown Worldwide ikukhumbuza ukuthi kunezimo ezimbili ezihlukene okufanele zicatshangelwe, isimo esibi kakhulu kanye nesimo sangempela. Sebenzisa isibalo esibi kakhulu ngoba lo mphumela uhlinzeka ngendawo enkulu yokuphepha futhi ungaqinisekisa ukuthi uhlelo ngeke lwehluleke.

II-MOSFETkancane kancane ithatha indawo ye-triode kumasekhethi ahlanganisiwe ngenxa yokusetshenziswa kwayo okuphansi kwamandla, ukusebenza okuzinzile, nokumelana nemisebe. Kodwa isethambile kakhulu, futhi nakuba iningi lazo selivele linama-diode okuvikela akhelwe ngaphakathi, lingalimala uma linganakekelwa. Ngakho-ke, kungcono kakhulu ukudinga ukuqaphela ekusetshenzisweni futhi.