Umthamo wesango, ukuxhathisa kunye nezinye iiparamitha zeMOSFETs

I. Umthamo wesango

Umthamo wesango ikakhulu ubandakanya amandla okufakwayo (iCiss), amandla okuvelisa (i-Coss) kunye ne-reverse transfer capacitance (i-Crss, eyaziwa ngokuba yi-Miller capacitance).

 

Umthamo wegalelo (Ciss):

 

INGCACISO: I-input capacitance yi-capacitance epheleleyo phakathi kwesango kunye nomthombo kunye ne-drain, kwaye iqulethe i-capacitance yomthombo wesango (Cgs) kunye ne-gate drain capacitance (Cgd) exhunywe ngokufanayo, okt Ciss = Cgs + Cgd.

 

Umsebenzi: I-input capacitance ichaphazela isantya sokutshintsha kwe-MOSFET. Xa i-input capacitance ihlawuliswa kwi-voltage threshold, isixhobo sinokuvulwa; ukukhutshwa kwixabiso elithile, isixhobo sinokucinywa. Ngoko ke, isekethe yokuqhuba kunye neCiss inefuthe elithe ngqo kwisixhobo sokuvula kunye nokulibaziseka kokucima.

 

Umthamo wemveliso (Indleko):

Inkcazo: I-output capacitance yi-capacitance epheleleyo phakathi kwe-drain kunye nomthombo, kwaye iqulethe i-drain-source capacitance (Cds) kunye ne-gate-drain capacitance (Cgd) ngokufanayo, oko kukuthi i-Coss = Cds + Cgd.

 

Indima: Kwizicelo zokutshintsha okuthambileyo, i-Coss ibaluleke kakhulu kuba inokubangela i-resonance kwisekethe.

 

UReverse Transmission Capacitance (Crss):

Inkcazo: I-reverse transfer capacitance ilingana ne-gate drain capacitance (Cgd) kwaye idla ngokubizwa ngokuba yiMiller capacitance.

 

Indima: I-reverse transfer capacitance yiparameter ebalulekileyo yokunyuka nokuwa kwexesha lokutshintsha, kwaye ichaphazela ixesha lokulibaziseka kokucima. Ixabiso le-capacitance liyancipha njengoko i-voltage ye-drain-source inyuka.

II. Ukuxhathisa (kwi-Rds(kwi))

 

Ingcaciso: Ukumelana ne-on-resistant kuxhathiso phakathi komthombo kunye ne-drain ye-MOSFET kwimeko-bume phantsi kweemeko ezithile (umz., ukuvuza okuthe ngqo kwangoku, umbane wesango, kunye nobushushu).

 

Izinto ezichaphazelayo: Ukumelana ne-on-resistance akulona ixabiso elimiselweyo, lichaphazelekayo ngubushushu, ubushushu obuphezulu, ubukhulu be-Rds (on). Ukongeza, okukhona uphezulu amandla ombane wokuxhathisa, kokukhona ukuqina kolwakhiwo lwangaphakathi lweMOSFET, kokukhona kunyuka ukuchasana okuhambelanayo.

 

 

Ukubaluleka: Xa uyila umbane otshintshayo okanye isekethe yomqhubi, kuyafuneka ukuba kuthathelwe ingqalelo ukuxhathisa kwe-MOSFET, kuba ikhoyo ngoku equkuqelayo nge-MOSFET iya kusebenzisa amandla kolu xhathiso, kwaye le nxalenye yamandla asetyenzisiweyo ibizwa ngokuba- ilahleko yokuxhathisa. Ukukhetha i-MOSFET enokumelana okuphantsi kunokunciphisa ilahleko yokunganyangeki.

 

Okwesithathu, ezinye iiparamitha ezibalulekileyo

Ukongeza kubuchule besango kunye nokumelana, i-MOSFET inezinye iiparamitha ezibalulekileyo ezinje:

I-V(BR)DSS (i-Drain Source Breakdown Voltage):I-voltage yomthombo we-drain apho i-current ejikelezayo kwi-drain ifikelela kwixabiso elithile kwiqondo lokushisa elithile kunye nomthombo wesango ufutshane. Ngaphezulu kweli xabiso, ityhubhu inokonakala.

 

VGS(th) (Threshold Voltage):Umbane wesango ofunekayo ukuze wenze umjelo wokuqhuba uqalise ukwenza phakathi komthombo kunye ne-drain. Kumgangatho we-N-channel MOSFETs, i-VT imalunga ne-3 ukuya kwi-6V.

 

I-ID (Obona Phezulu buQhubayo boMfunxa ngoku):Ubuninzi obuqhubekayo be-DC obukhoyo obunokuvunyelwa yi-chip kwiqondo lobushushu eliphezulu le-junction.

 

I-IDM (Obona Bubona Phezulu boMbhobho woMbhobho wangoku):Ibonakalisa inqanaba le-pulsed yangoku esinokuthi isixhobo sikwazi ukuyiphatha, kunye ne-pulsed yangoku iphezulu kakhulu kune-DC eqhubekayo yangoku.

 

I-PD (ubona buninzi bokutshatyalaliswa kwamandla):isixhobo sinokuchitha ukusetyenziswa kwamandla aphezulu.

 

Isishwankathelo, amandla esango, ukuchasana kunye nezinye iiparamitha ze-MOSFET zibaluleke kakhulu ekusebenzeni kwayo kunye nokusetyenziswa kwayo, kwaye kufuneka zikhethwe kwaye ziyilwe ngokweemeko ezithile kunye neemfuno.