Me yasa yake da wahala koyaushe don gwada amfani da MOSFET mai ƙarfi da maye gurbin tare da multimeter?

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Me yasa yake da wahala koyaushe don gwada amfani da MOSFET mai ƙarfi da maye gurbin tare da multimeter?

Game da babban iko MOSFET ya kasance ɗaya daga cikin injiniyoyin da ke sha'awar tattauna batun, don haka mun tsara ilimin gama gari da na kowa.MOSFET, Ina fatan in taimaki injiniyoyi. Bari mu yi magana game da MOSFET, wani muhimmin sashi!

Anti-static kariya

MOSFET mai ƙarfi mai ƙarfi shine bututun filin filin ƙofar da aka keɓe, ƙofar ba ta da da'ira kai tsaye, impedance ɗin shigarwa yana da girma sosai, yana da sauƙaƙa don haifar da tarawar cajin a tsaye, wanda ke haifar da babban ƙarfin lantarki zai zama ƙofar kuma tushen tushen. da insulating Layer tsakanin rushewa.

Yawancin farkon samar da MOSFETs ba su da matakan kariya, don haka a kula sosai a wurin tsarewa da aikace-aikacen, musamman ma ƙaramin ƙarfin MOSFETs, saboda ƙaramin ƙarfin shigar da MOSFET yana da ɗan ƙaramin ƙarfi, lokacin da aka fallasa wutar lantarki a tsaye yana haifar da mafi girma irin ƙarfin lantarki, sauƙi lalacewa ta hanyar electrostatic rushewa.

Haɓaka na baya-bayan nan na MOSFET mai ƙarfi yana da ɗan bambanci, da farko, saboda aikin babban ƙarfin shigar da ƙara shima ya fi girma, ta yadda tuntuɓar wutar lantarki a tsaye yana da tsarin caji, yana haifar da ƙaramin ƙarfin lantarki, yana haifar da lalacewa. na yuwuwar ƙarami, sannan kuma, yanzu MOSFET mai ƙarfi a cikin ƙofar ciki da tushen kofa da tushen mai sarrafa DZ mai karewa, a tsaye da aka saka a cikin kariyar ƙimar ƙimar wutar lantarki mai sarrafa diode ƙasa, yadda ya kamata. kare ƙofa da tushen rufin rufin, iko daban-daban, nau'ikan nau'ikan MOSFET mai kariyar kariyar diode ƙimar wutar lantarki ta bambanta.

Kodayake manyan matakan kariya na MOSFET na cikin gida, ya kamata mu yi aiki daidai da ka'idojin aiki na anti-static, wanda ƙwararrun ma'aikatan kulawa yakamata su sami.

Ganewa da sauyawa

A cikin gyaran talabijin da na'urorin lantarki, za su haɗu da lalacewa iri-iri,MOSFETHar ila yau, yana cikin su, wanda shine yadda ma'aikatanmu masu kula da su za su yi amfani da multimeter da aka saba amfani da su don tantance mai kyau da mara kyau, mai kyau da mara kyau MOSFET. A cikin maye gurbin MOSFET idan babu masana'anta iri ɗaya da samfurin iri ɗaya, yadda ake maye gurbin matsalar.

 

1, Gwajin MOSFET mai ƙarfi:

A matsayin ma'aikatan gyaran gyare-gyare na TV na yau da kullum a cikin ma'auni na transistor ko diodes, gabaɗaya ta yin amfani da multimeter na yau da kullun don ƙayyade mai kyau da mara kyau transistor ko diodes, kodayake ba za a iya tabbatar da ma'aunin lantarki na transistor ko diode ba, amma muddin Hanyar daidai ce don tabbatar da transistor crystal "mai kyau" da "mara kyau" ko "mara kyau" don tabbatar da transistor crystal. "Bad" ko babu matsala. Hakanan, MOSFET na iya zama

Don amfani da multimeter don ƙayyade "mai kyau" da "mara kyau", daga kulawa na gaba ɗaya, kuma na iya biyan bukatun.

Gano dole ne a yi amfani da nau'in mai nuna alama multimeter (mita na dijital bai dace da auna na'urorin semiconductor ba). Don nau'in MOSFET mai canzawa bututu sune haɓaka tashoshi N-tashar, samfuran masana'antun kusan duk suna amfani da nau'in fakitin TO-220F iri ɗaya (yana nufin canjin wutar lantarki don ikon 50-200W na tasirin tasirin filin sauya bututu) , Tsarin lantarki guda uku shima daidai yake, wato uku

Fitar ƙasa, samfurin buga yana fuskantar kai, fil ɗin hagu don ƙofar, fil ɗin gwajin dama don tushen, fil na tsakiya don magudanar ruwa.

(1) multimeter da shirye-shirye masu alaƙa:

Da farko, kafin auna ya kamata a iya amfani da multimeter, musamman aikace-aikace na ohm gear, don gane da ohm block zai zama daidai aikace-aikace na ohm block don auna crystal transistor kuma.MOSFET.

Tare da multimeter ohm block ohm sikelin cibiyar ba zai iya girma da yawa ba, zai fi dacewa ƙasa da 12 Ω (nau'in tebur na 500 don 12 Ω), ta yadda a cikin toshe R × 1 na iya samun babban halin yanzu, don haɗin PN na gaba. halaye na hukunci ya fi daidai. Multimeter R × 10K toshe baturi na ciki ya fi 9V mafi kyau, ta yadda a auna ma'aunin PN junction inverse leaka halin yanzu ya fi daidai, in ba haka ba ba za a iya auna zubin ba.

Yanzu saboda ci gaban da samar da tsari, da masana'anta nunawa, gwaji ne sosai m, mu kullum yin hukunci idan dai hukuncin MOSFET ba yayyo, ba ya karya ta cikin gajeren kewaye, da ciki ba kewaye, na iya zama. Ƙaddamar da hanya, hanyar tana da sauƙi:

Amfani da multimeter R × 10K block; R × 10K toshe baturi na ciki shine gabaɗaya 9V da 1.5V zuwa 10.5V wannan ƙarfin wutar lantarki gabaɗaya ana yanke hukunci ya zama isassun junction junction na PN, alƙalamin ja na multimeter shine mummunan yuwuwar (an haɗa shi da mummunan tashar baturi na ciki), baƙar alkalami na multimeter yana da tabbataccen yuwuwar (haɗe zuwa ingantaccen tasha na baturi na ciki).

(2) Hanyar gwaji:

Haɗa alkalami ja zuwa tushen MOSFET S; haɗa bakin alkalami zuwa magudanar ruwa na MOSFET D. A wannan lokacin, alamar allura ya kamata ya zama marar iyaka. Idan akwai alamar ohmic, yana nuna cewa bututun da ake gwadawa yana da abin yabo, ba za a iya amfani da wannan bututun ba.

Kula da yanayin da ke sama; a wannan lokacin tare da resistor 100K ~ 200K da aka haɗa da ƙofar da magudanar ruwa; a wannan lokaci allura ya kamata ya nuna adadin ohms mafi ƙarami, gabaɗaya ana iya nuna shi zuwa 0 ohms, wannan lokacin yana da caji mai kyau ta hanyar resistor 100K akan cajin ƙofar MOSFET, yana haifar da filin lantarki na ƙofar, saboda wutar lantarki da aka samar ta hanyar tashar sarrafawa wanda ke haifar da magudanar ruwa da kuma samar da tushen, don haka ƙaddamarwar allurar multimeter, kusurwar jujjuyawa yana da girma (Ohm's index yana da ƙananan) don tabbatar da cewa aikin fitarwa yana da kyau.

Sa'an nan kuma haɗa zuwa resistor cire, sa'an nan multimeter nuna alama ya kamata har yanzu MOSFET a kan index ya kasance ba canzawa. Ko da yake resistor ya dauke, amma saboda resistor zuwa gate cajin da cajin ba ya bace, ƙofar lantarki filin na ci gaba da kula da ciki conductive tashar har yanzu kiyaye, wanda shi ne halaye na insulated kofa irin MOSFET.

Idan resistor ya dauke allurar zai sannu a hankali kuma sannu a hankali ya koma babban juriya ko ma ya koma mara iyaka, don la'akari da cewa kwararar ƙofar bututu da aka auna.

A wannan lokacin tare da waya, an haɗa shi da ƙofar da tushen bututun a ƙarƙashin gwaji, mai nuna multimeter nan da nan ya koma marar iyaka. Haɗin waya don MOSFET da aka auna, sakin cajin ƙofar, filin lantarki na ciki ya ɓace; tashar gudanarwa kuma tana ɓacewa, don haka magudanar ruwa da tushen tsakanin juriya kuma ya zama marar iyaka.

2, maye gurbin MOSFET mai ƙarfi

A cikin gyare-gyaren talabijin da kowane nau'i na kayan lantarki, ya kamata a maye gurbin lalacewar abubuwan da ke faruwa tare da nau'in nau'i iri ɗaya. Duk da haka, wani lokacin guda aka gyara ba a hannun, shi wajibi ne don amfani da wasu nau'i na maye gurbin, don haka dole ne mu yi la'akari da dukan al'amurran da aiki, sigogi, girma, da dai sauransu, kamar talabijin a cikin line fitarwa tube, kamar yadda. muddin la'akari da irin ƙarfin lantarki, halin yanzu, ikon iya kullum maye gurbinsu (line fitarwa tube kusan iri daya girma na bayyanar), da kuma ikon oyan ya zama mafi girma da kuma mafi kyau.

Don maye gurbin MOSFET, kodayake kuma wannan ka'ida, yana da kyau a gwada mafi kyawun, musamman, kar ku bi ikon da ya fi girma, saboda ikon yana da girma; karfin shigar da shigar yana da girma, canzawa da da'irori masu motsa rai ba su dace da tashin hankali na cajin halin yanzu mai iyakance resistor na da'irar ban ruwa na girman ƙimar juriya da ƙarfin shigar da MOSFET yana da alaƙa da zaɓin ikon manyan duk da iya aiki mai girma, amma ƙarfin shigar da shi kuma yana da girma, kuma ƙarfin shigarwar kuma yana da girma, kuma ƙarfin ba shi da girma.

Har ila yau ƙarfin shigar da bayanai yana da girma, yanayin motsa jiki ba shi da kyau, wanda hakan zai sa MOSFET ta kunna da kashe aikin. Yana nuna maye gurbin nau'ikan MOSFET daban-daban, la'akari da ƙarfin shigar da wannan siga.

Misali, akwai 42-inch LCD TV backlight high-voltage board lalacewa, bayan duba na ciki high-ikon MOSFET lalacewa, saboda babu samfurin adadin maye, da zabi na wani irin ƙarfin lantarki, halin yanzu, iko ba kasa da Musanya MOSFET na asali, sakamakon shine bututun hasken baya ya bayyana a matsayin ci gaba da flicker (matsalolin farawa), kuma a ƙarshe an maye gurbinsu da nau'in asali iri ɗaya don magance matsalar.

Lalacewar da aka gano ga MOSFET mai ƙarfi, dole ne a maye gurbin abubuwan da ke gefensa na kewayen perfusion ɗin, saboda lalacewar MOSFET ɗin na iya zama maras kyau abubuwan da'irar perfusion da lalacewa ga MOSFET ta haifar. Ko da MOSFET da kanta ta lalace, lokacin da MOSFET ta rushe, abubuwan da'irar perfusion suma suna cutarwa kuma yakamata a canza su.

Kamar dai yadda muke da ƙwararrun ƙwararrun ƙwararrun gyare-gyare a cikin gyaran wutar lantarki na A3 mai sauyawa; idan dai an gano bututun sauyawa ya rushe, kuma shine gaban bututun motsa jiki na 2SC3807 tare da maye gurbin wannan dalili (ko da yake bututun 2SC3807, wanda aka auna tare da multimeter yana da kyau).


Lokacin aikawa: Afrilu-15-2024