Jagorori don Zaɓin Kunshin MOSFET

Na biyu, girman iyakokin tsarin

Wasu tsarin lantarki suna iyakance ta girman PCB da na ciki tsawo, skamar tsarin sadarwa, samar da wutar lantarki na zamani saboda iyakokin tsayi yawanci suna amfani da kunshin DFN5 * 6, DFN3 * 3; a cikin wasu samar da wutar lantarki na ACDC, yin amfani da ƙira mai ƙarancin ƙarfi ko kuma saboda ƙarancin harsashi, taron kunshin TO220 na ƙafafun MOSFET mai ƙarfi wanda aka saka kai tsaye cikin tushen iyakokin tsayin daka ba zai iya amfani da kunshin TO247 ba. Wasu ƙwaƙƙwaran ƙira kai tsaye suna lanƙwasa fil ɗin na'urar lebur, wannan tsarin samar da ƙira zai zama mai rikitarwa.

Na uku, tsarin samar da kamfanin

TO220 yana da nau'i biyu na kunshin ƙarfe da cikakkiyar kunshin ƙarfe da cikakken kunshin filastik ya karu, amma a cikin tsarin samarwa yana da ƙarfi, amma a cikin tsarin samarwa yana da ƙarfi, amma a cikin tsarin samarwa yana da ƙarfi, tsari mai lalacewa, tsarin samarwa yana da haɗari da tsada, yayin da cikakken juriyar zafin jiki na fakitin filastik yana da girma, ƙarancin zafi yana da rauni, amma tsarin samarwa yana da sauƙi.

Don rage tsarin wucin gadi na kulle sukurori, a cikin 'yan shekarun nan, wasu na'urorin lantarki suna amfani da shirye-shiryen bidiyo zuwa wutaMOSFETs clamped a cikin zafi nutse, sabõda haka, fitowan na gargajiya TO220 part na babba kashi na cire ramuka a cikin sabon nau'i na encapsulation, amma kuma don rage tsawo na na'urar.

Na hudu, kula da farashi

A cikin wasu aikace-aikace masu matuƙar tsada kamar su motherboards da allo, ana amfani da MOSFET masu ƙarfi a cikin fakitin DPAK saboda ƙarancin farashin irin waɗannan fakitin. Sabili da haka, lokacin zabar kunshin MOSFET mai ƙarfi, haɗe tare da salon kamfaninsu da fasalin samfuran, kuma kuyi la'akari da abubuwan da ke sama.

Na biyar, zaɓi ƙarfin ƙarfin juriya BVDSS a mafi yawan lokuta, saboda ƙirar shigarwar voltage na lantarki tsarin yana da ƙayyadaddun ƙayyadaddun ƙayyadaddun ƙayyadaddun kayan aiki, kamfanin ya zaɓi takamaiman mai ba da lambar kayan aiki, ƙimar ƙarfin samfurin kuma an gyara shi.

Rushewar wutar lantarki BVDSS na wutar lantarki MOSFETs a cikin bayanan bayanan ya bayyana yanayin gwaji, tare da ƙima daban-daban a ƙarƙashin yanayi daban-daban, kuma BVDSS yana da ƙimar zafin jiki mai kyau, a cikin ainihin aikace-aikacen haɗin waɗannan abubuwan yakamata a yi la'akari da su cikin cikakkiyar hanya.

Yawancin bayanai da wallafe-wallafe sau da yawa ana ambata: idan tsarin wutar lantarki MOSFET VDS na mafi girman ƙarfin lantarki idan ya fi BVDSS, koda kuwa tsawon lokacin ƙarfin bugun jini na 'yan kaɗan ko dubun ns, ikon MOSFET zai shiga cikin dusar ƙanƙara. don haka lalacewa ta faru.

Ba kamar transistors da IGBT ba, MOSFET masu ƙarfi suna da ikon yin tsayayya da bala'in bala'i, kuma yawancin manyan kamfanonin semiconductor suna ba da ƙarfin MOSFET avalanche makamashi a cikin layin samarwa shine cikakken dubawa, gano 100%, wato, a cikin bayanan wannan tabbataccen ma'auni ne, wutar lantarki mai dusar ƙanƙara. yawanci yana faruwa a cikin 1.2 ~ 1.3 sau BVDSS, kuma tsawon lokacin shine yawanci μs, har ma da matakin ms, sannan Tsawon ƴan kaɗan ko dubun ns, ƙasa da ƙanƙara fiye da ƙanƙarar ƙarfin ƙarfin bugun bugun bugun jini baya lalacewa ga wutar MOSFET.

Shida, ta hanyar zaɓin ƙarfin lantarki VTH

Daban-daban tsarin lantarki na iko MOSFETs zaba drive irin ƙarfin lantarki ba iri daya ba, AC / DC samar da wutar lantarki yawanci amfani da 12V drive irin ƙarfin lantarki, da littafin rubutu ta motherboard DC / DC Converter ta amfani da 5V drive ƙarfin lantarki, don haka bisa ga tsarin ta drive ƙarfin lantarki don zaɓar wani daban-daban kofa irin ƙarfin lantarki. VTH ikon MOSFETs.

Matsakaicin ƙarfin wutar lantarki VTH na MOSFETs mai ƙarfi a cikin bayanan bayanan shima ya ayyana yanayin gwaji kuma yana da ƙima daban-daban a ƙarƙashin yanayi daban-daban, kuma VTH yana da ƙarancin zafin jiki mara kyau. Daban-daban irin ƙarfin lantarki VGS sun dace da nau'ikan juriya daban-daban, kuma a cikin aikace-aikacen aikace-aikacen yana da mahimmanci a la'akari da zafin jiki.

A aikace-aikace masu amfani, ya kamata a yi la'akari da bambancin zafin jiki don tabbatar da cewa MOSFET ta kunna gabaɗaya, yayin da a lokaci guda tabbatar da cewa ƙwanƙolin karu da aka haɗe da G-pole yayin tsarin rufewa ba zai haifar da ruɗar ƙarya ba. samar da madaidaiciyar hanya ko gajeriyar kewayawa.