Demystifying Reverse Recovery mu MOSFET Body Diode

Pazinthu zamagetsi, ma MOSFETs (Metal-Oxide-Semiconductor Field-Effect Transistors) atulukira ngati zigawo zomwe zimapezeka paliponse, zodziwika bwino chifukwa cha mphamvu zake, kusintha kwachangu, ndi kuwongolera. Komabe, chibadwa cha ma MOSFET, diode ya thupi, imayambitsa chodabwitsa chomwe chimatchedwa reverse recovery, chomwe chingakhudze magwiridwe antchito a chipangizo ndi kapangidwe ka dera. Cholemba ichi chabulogu chimayang'ana dziko lakuchira mobwerera m'mbuyo mu ma diode a thupi la MOSFET, ndikuwunika momwe amagwirira ntchito, tanthauzo lake, komanso tanthauzo lake pamapulogalamu a MOSFET.

Kuvumbulutsa Njira Yobwezeretsanso Reverse

MOSFET ikazimitsidwa, zomwe zikuyenda kudzera munjira yake zimasokonezedwa mwadzidzidzi. Komabe, diode ya parasitic body, yopangidwa ndi mawonekedwe a MOSFET, imachita mosinthira momwe ndalama zosungidwa munjira zimayambiranso. Kubwereranso kumeneku, komwe kumadziwika kuti reverse recovery current (Irrm), kumawola pang'onopang'ono pakapita nthawi mpaka kukafika ziro, zomwe zikuwonetsa kutha kwa nthawi yobwezeretsanso (trr).

Zinthu Zomwe Zimayambitsa Kubwezeretsa Mmbuyo

Makhalidwe obwezeretsanso ma diode a MOSFET amatengera zinthu zingapo:

Kapangidwe ka MOSFET: Ma geometry, milingo ya doping, ndi zinthu zamkati za MOSFET zimagwira ntchito yayikulu pakuzindikira Irrm ndi trr.

Kagwiritsidwe Ntchito: Njira yobwezeretsanso imakhudzidwanso ndi momwe amagwirira ntchito, monga magetsi ogwiritsidwa ntchito, liwiro losinthira, ndi kutentha.

Kuzungulira Kwakunja: Zozungulira zakunja zolumikizidwa ndi MOSFET zimatha kukhudza njira yobwezeretsanso, kuphatikiza kukhalapo kwa mabwalo opumira kapena katundu wowonjezera.

Zotsatira za Kubwezeretsanso Kumbuyo kwa Mapulogalamu a MOSFET

Kubwezeretsanso kungayambitse zovuta zingapo pamapulogalamu a MOSFET:

Ma Spikes a Voltage: Kutsika kwadzidzidzi kwanthawi yayitali panthawi yobwezeretsa kungathe kupanga ma spikes amagetsi omwe amatha kupitilira mphamvu yakuwonongeka kwa MOSFET, kuwononga chipangizocho.

Kutayika kwa Mphamvu: Kubwezeretsanso komweku kumawononga mphamvu, kumabweretsa kutayika kwamagetsi ndi zovuta zomwe zingatenthedwe.

Phokoso Lozungulira: Njira yobwezeretsanso m'mbuyo imatha kulowetsa phokoso mudera, kusokoneza kukhulupirika kwa ma siginecha ndikupangitsa kuti pakhale zovuta m'mabwalo ovuta.

Kuchepetsa Zotsatira Zakuyambiranso

Kuti muchepetse zotsatira zoyipa za kubwezeretsanso, njira zingapo zingagwiritsidwe ntchito:

Maulendo a Snubber: Mabwalo a snubber, omwe amakhala ndi ma resistors ndi ma capacitor, amatha kulumikizidwa ku MOSFET kuti achepetse ma spikes amagetsi ndikuchepetsa kutayika kwa mphamvu panthawi yobwezeretsanso.

Njira Zosinthira Zofewa: Njira zosinthira zofewa, monga pulse-width modulation (PWM) kapena kusintha kwa resonant, zimatha kuwongolera kusintha kwa MOSFET pang'onopang'ono, kuchepetsa kuuma kwa kubwezeretsanso.

Kusankha ma MOSFET okhala ndi Low Reverse Recovery: Ma MOSFET okhala ndi Irrm yotsika ndi trr amatha kusankhidwa kuti achepetse kukhudzidwa kwa kubwezeretsanso magwiridwe antchito a dera.

Mapeto

Kubwezeretsanso kwa ma diode a thupi la MOSFET ndi chikhalidwe chomwe chimatha kukhudza magwiridwe antchito a chipangizocho komanso kapangidwe kake. Kumvetsetsa momwe zimagwirira ntchito, zomwe zimathandizira, komanso zomwe zimakhudza kubwezeretsanso ndikofunikira pakusankha ma MOSFET oyenera ndikugwiritsa ntchito njira zochepetsera kuti muwonetsetse kuti dera likuyenda bwino komanso kudalirika. Pamene ma MOSFET akupitilizabe kugwira ntchito yofunika kwambiri pamakina amagetsi, kuthana ndi kuchira kumakhalabe gawo lofunikira pakupanga madera ndi kusankha zida.