Dalilai da Rigakafin gazawar MOSFET

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Dalilai da Rigakafin gazawar MOSFET

Manyan dalilai guda biyuof MOSFET gazawa:

Rashin wutar lantarki: wato, ƙarfin lantarki na BVdss tsakanin magudanar ruwa da tushen ya zarce ƙimar ƙarfin lantarki naMOSFET kuma ya kai wani iya aiki, yana haifar da MOSFET ta gaza.

Rashin Wutar Lantarki na Ƙofar: Ƙofar tana fama da ƙarancin ƙarfin lantarki, wanda ya haifar da gazawar Layer na ƙofar oxygen.

Dalilai da Rigakafin gazawar MOSFET

Rushe kuskure ( gazawar wutar lantarki)

Menene ainihin lalacewar dusar ƙanƙara? A taƙaice,da MOSFET yanayin gazawa ne da aka ƙirƙira ta babban matsayi tsakanin ƙarfin bas, wutar lantarki mai jujjuyawar wuta, ƙyalli mai ƙyalli, da sauransu da MOSFET. A takaice, gazawa ce ta gama gari wacce ke faruwa a lokacin da wutar lantarki a magudanar ruwa ta MOSFET ta wuce ƙayyadaddun ƙimar ƙarfin lantarki da ta kai ga wani ƙayyadaddun makamashi.

 

Matakan don hana ɓarna avalanche:

-Rage maganin da ya dace. A cikin wannan masana'antar, yawanci ana rage shi da 80-95%. Zaɓi dangane da sharuɗɗan garanti na kamfani da fifikon layi.

-Tsarin wutar lantarki yana da ma'ana.

-RCD, TVS shawar kewaye zane yana da ma'ana.

-Maɗaukakin wayoyi na yanzu yakamata ya zama babba kamar yadda zai yiwu don rage inductance parasitic.

-Zaɓi mai tsayayyar kofa mai dacewa Rg.

-Ƙara damping RC ko sha na Zener diode don babban kayan wuta kamar yadda ake buƙata.

Dalilai da Rigakafin gazawar MOSFET(1)

Rashin Gashin Wutar Lantarki na Ƙofar

Akwai manyan dalilai guda uku na manyan ƙarfin wutar lantarki waɗanda ba su saba ba: wutar lantarki a tsaye yayin samarwa, sufuri da taro; high ƙarfin lantarki resonance samar da parasitic sigogi na kayan aiki da da'irori a lokacin da ikon tsarin aiki; da kuma watsa babban ƙarfin lantarki ta hanyar Ggd zuwa grid yayin babban girgizar wutar lantarki (laifi da ya fi yawa yayin gwajin yajin walƙiya).

 

Matakan don hana lalacewar wutar lantarki na ƙofa:

Overvoltage kariya tsakanin kofa da tushen: Lokacin da impedance tsakanin kofa da tushen ya yi yawa, kwatsam canji a cikin ƙarfin lantarki tsakanin ƙofar da tushen yana haɗe zuwa ƙofar ta hanyar capacitance tsakanin na'urorin lantarki, wanda ya haifar da babban ƙarfin UGS akan-ka'ida, yana haifar da over-regulation na ƙofar. Lalacewar oxidative na dindindin. Idan UGS yana kan ingantaccen ƙarfin lantarki na wucin gadi, na'urar kuma na iya haifar da kurakurai. A kan wannan dalili, ya kamata a rage girman da'irar ƙofa ta hanyar da kyau kuma a haɗa damping resistor ko 20V ƙarfafa ƙarfin lantarki tsakanin ƙofar da tushen. Yakamata a kula musamman don hana bude kofa.

Kariyar wuce gona da iri tsakanin bututun fitarwa: Idan akwai inductor a cikin da'irar, canje-canje kwatsam a cikin ɗigogi na yanzu (di/dt) lokacin da aka kashe naúrar zai haifar da ɗigon wutar lantarki ya yi sama da ƙarfin wutar lantarki, yana haifar da lalacewa ga naúrar. Kariya yakamata ya haɗa da matsi na Zener, RC clamp, ko da'irar suppression RC.


Lokacin aikawa: Yuli-17-2024