Wuraren Zabin MOSFET

ZabinMOSFETYana da matukar muhimmanci, mummunan zaɓe na iya yin tasiri ga amfani da wutar lantarki na gabaɗayan da'ira, ƙware nau'ikan abubuwan MOSFET daban-daban da sigogi a cikin da'irori daban-daban na iya taimakawa injiniyoyi su guje wa matsaloli masu yawa, waɗannan sune wasu shawarwarin Guanhua Weiye. don zaɓin MOSFETs.

Na farko, P-channel da N-channel

Mataki na farko shine ƙayyade amfani da N-channel ko P-channel MOSFETs. a cikin aikace-aikacen wutar lantarki, lokacin da MOSFET ƙasa, da kuma nauyin da aka haɗa da wutar lantarki, daMOSFETya ƙunshi ƙananan wutan lantarki. A cikin ƙananan jujjuyawar gefen wuta, ana amfani da MOSFETs N-channel gabaɗaya, wanda shine la'akari da ƙarfin lantarki da ake buƙata don kashe ko kunna na'urar. Lokacin da MOSFET ta haɗa da bas da ƙasa mai kaya, ana amfani da babban ƙarfin wutan gefe. P-tashar MOSFETs yawanci ana amfani da su, saboda la'akari da tuƙin wutar lantarki. Don zaɓar abubuwan da suka dace don aikace-aikacen, yana da mahimmanci don ƙayyade ƙarfin lantarki da ake buƙata don fitar da na'urar da yadda sauƙin aiwatarwa a cikin ƙira. Mataki na gaba shine tantance ƙimar ƙarfin lantarki da ake buƙata, ko matsakaicin ƙarfin wutar lantarki da sashin zai iya ɗauka. Mafi girman ƙimar ƙarfin lantarki, mafi girman farashin na'urar. A aikace, ƙimar ƙarfin lantarki ya kamata ya fi ƙarfin akwati ko bas. Wannan zai ba da isasshen kariya ta yadda MOSFET ba za ta gaza ba. Don zaɓin MOSFET, yana da mahimmanci don ƙayyade matsakaicin ƙarfin lantarki wanda za a iya jurewa daga magudanar ruwa zuwa tushe, watau, matsakaicin VDS, don haka yana da mahimmanci a san cewa matsakaicin ƙarfin da MOSFET zai iya jurewa ya bambanta da zafin jiki. Masu ƙira suna buƙatar gwada kewayon ƙarfin lantarki akan duk kewayon zafin aiki. Wutar lantarki da aka ƙididdige yana buƙatar samun isassun tazara don rufe wannan kewayon don tabbatar da cewa kewaye ba ta gaza ba. Bugu da kari, wasu dalilai na aminci suna buƙatar la'akari da jajircewar wutar lantarki.

Na biyu, ƙayyade ƙimar halin yanzu

Mahimman ƙima na MOSFET na yanzu ya dogara da tsarin kewayawa. Ƙimar halin yanzu shine matsakaicin halin yanzu wanda kaya zai iya jurewa a ƙarƙashin kowane yanayi. Hakazalika da yanayin wutar lantarki, mai ƙira yana buƙatar tabbatar da cewa MOSFET da aka zaɓa tana da ikon ɗaukar wannan ƙimar halin yanzu, ko da lokacin da tsarin ke haifar da ƙarar halin yanzu. Yanayin yanayi biyu na yanzu da za a yi la'akari da su sune yanayin ci gaba da bugun bugun jini. MOSFET yana cikin tsayayyen yanayi a ci gaba da tafiyar da yanayin, lokacin da halin yanzu ke wucewa ta na'urar. Pulse spikes yana nufin adadi mai yawa na hawan (ko spikes na halin yanzu) da ke gudana ta cikin na'urar, a cikin wannan yanayin, da zarar an ƙayyade matsakaicin halin yanzu, kawai batun zaɓin na'urar kai tsaye wanda zai iya jure wannan matsakaicin halin yanzu.

Bayan zaɓin ƙimar halin yanzu, asarar gudanarwa kuma ana ƙididdige shi. A wasu lokuta,MOSFETba su dace da abubuwan da suka dace ba saboda asarar wutar lantarki da ke faruwa a yayin aikin gudanarwa, abin da ake kira hasarar tafiyarwa. Lokacin "kunna", MOSFET yana aiki azaman resistor mai canzawa, wanda RDS(ON) na na'urar ya ƙaddara kuma yana canzawa sosai tare da zafin jiki. Ana iya ƙididdige asarar wutar lantarki daga Iload2 x RDS(ON), kuma tun da juriya ya bambanta da zafin jiki, asarar wutar ta bambanta daidai gwargwado. Mafi girman ƙarfin wutar lantarki VGS da ake amfani da shi zuwa MOSFET, ƙananan RDS (ON); Sabanin haka, mafi girman RDS(ON). Ga mai tsara tsarin, wannan shine inda kasuwancin ke shiga cikin wasa dangane da ƙarfin tsarin. Don ƙirar šaukuwa, ƙananan ƙarfin lantarki sun fi sauƙi (kuma mafi yawan gama gari), yayin da don ƙirar masana'antu, ana iya amfani da ƙarfin lantarki mafi girma. Lura cewa juriya na RDS(ON) yana tashi kaɗan tare da halin yanzu.

Fasaha tana da tasiri mai girma akan halayen sassa, kuma wasu fasahohin kan haifar da haɓaka RDS(ON) yayin daɗa mafi girman VDS. Don irin waɗannan fasahohin, ana buƙatar haɓaka girman wafer idan za a saukar da VDS da RDS (ON), don haka ƙara girman fakitin da ke tare da shi da ƙimar haɓaka daidai. Akwai fasahohi da yawa a cikin masana'antar da ke ƙoƙarin sarrafa haɓakar girman wafer, mafi mahimmancin su shine maɓalli da cajin fasahar ma'auni. A cikin fasahar maɓalli, rami mai zurfi yana cikin wafer, yawanci ana tanada shi don ƙananan ƙarfin lantarki, don rage juriya RDS(ON).

III. Ƙayyade buƙatun zubar da zafi

Mataki na gaba shine ƙididdige buƙatun thermal na tsarin. Ya kamata a yi la'akari da yanayi daban-daban guda biyu, mafi muni da kuma ainihin lamarin. TPV yana ba da shawarar ƙididdige sakamakon don mafi munin yanayi, saboda wannan lissafin yana ba da mafi girman gefen aminci kuma yana tabbatar da cewa tsarin ba zai gaza ba.

IV. Ayyukan Canjawa

A ƙarshe, aikin sauyawa na MOSFET. Akwai sigogi da yawa waɗanda ke shafar aikin sauyawa, masu mahimmanci sune ƙofar / magudanar ruwa, kofa / tushe da magudanar ruwa / iyawar tushen. Wadannan capacitances suna haifar da asarar canzawa a cikin sashin saboda buƙatar cajin su duk lokacin da aka kunna su. Sakamakon haka, saurin sauyawa na MOSFET yana raguwa kuma ingancin na'urar yana raguwa. Don ƙididdige yawan asarar da ke cikin na'urar yayin sauyawa, mai ƙirar yana buƙatar ƙididdige asarar lokacin kunnawa (Eon) da asarar yayin kashewa (Eoff). Ana iya bayyana wannan ta hanyar ma'auni mai zuwa: Psw = (Eon + Eoff) x mitar sauyawa. Kuma cajin kofa (Qgd) yana da tasiri mafi girma akan sauya aikin.