Unganquma kanjani ukuthi i-MOSFET yinhle noma yimbi?

Kunezindlela ezimbili zokutshela umehluko phakathi kwe-MOSFET enhle nembi:
Esokuqala: hlukanisa ngekhwalithi izinzuzo nezingozi zeAma-MOSFET

Okokuqala sebenzisa i-multimeter R × 10kΩ block (ibhethri elishumekiwe elingu-9V noma elingu-15V), ipeni elinegethivu (elimnyama) elixhunywe esangweni (G), ipeni eliphozithivu (elibomvu) elixhunywe kumthombo (S). Esangweni, umthombo wokushaja kwebhethri emaphakathi, kei-multimeter inaliti inokuchezuka okuncane. Bese ushintshela ku-multimeter R × 1Ω block,okubi ipeni ku-drain (D), ipeni elihle kumthombo (S), inani elibhalwe nge-multimeter uma umama ohm ambalwa, libonisa ukuthi i-MOSFET yinhle.

Unganquma kanjani ukuthi i-MOSFET yinhle noma yimbi

Owesibili: ukuxazulula ngokufanelekile izinga likagesi lama-MOSFET ahlanganayoI-multimeter izodayela kufayela le-R × 100, ipeni elibomvu lixhunywe ngokungahleliwe ku-tube yonyawo, ipeni elimnyama lixhunywe kwelinye ithubhu lezinyawo, ukuze unyawo lwesithathu lulengiswe emoyeni. Uma uthola ukuthi inaliti has a enyakaza kancane, kuqinisekiswa ukuthi unyawo lwesithathu for esangweni. Ukuze uthole ukuqashelwa okuphawulekayo komphumela wangempela, kodwa futhi nokudlidliza kwe-electronic eduze noma ngokuthinta umunwe kulenga ezinyaweni zomoya, ukubona kuphela inaliti yokuchezuka okukhulu, okusho ukuthi, okubonisa ukuthi ukulenga ezinyaweni zomoya kuyisango. , ezinye izinyawo ezimbili zaziwumthombo nomsele.

Izizathu ezihlukanisayo:

Ukumelana nokokufaka kwe-JFET kungaphezu kuka-100MΩ, futhi i-transconductance iphakeme kakhulu, lapho isango liholela endaweni yasendlini indawo kazibuthe kulula kakhulu ukunxenxa isignali yedatha ye-voltage esebenzayo esangweni, ukuze ipayipi lithambekele ekubeni lifinyelele, noma lithambekele. ukuba on-off. Uma i-voltage yokungeniswa komzimba yengezwa ngokushesha esangweni, ngoba ukuphazamiseka okubalulekile kwe-electromagnetic kunamandla, isimo esingenhla sizoba sibaluleke kakhulu. Uma inaliti yemitha engakwesokunxele sokuchezuka okukhulu, egameni lepayipi ijwayele ukunwetshwa kwe-RDS ye-drain-source resistor, inani lamanje le-drain-source ye-IDS encishisiwe. ngokuphambene, inaliti yemitha kwesokudla sokuchezuka okukhulu, okubonisa ukuthi ipayipi ivamise ukucisha, RDS ↓, IDS ↑. Kodwa-ke, inaliti yemitha ekugcineni ibheke ngakuphi ukuchezuka, kufanele incike ezigxotsheni ezinhle nezimbi ze-voltage eyenziwe (isiqondiso esihle se-voltage yokusebenza noma isiqondiso esiphambene se-voltage yokusebenza) kanye nendawo yokusebenza yepayipi yensimbi.
Imixwayiso:
(1) Ukuhlolwa kukhombisa ukuthi lapho izandla zombili zivaleleke ezigxotsheni zika-D no-S futhi kuthintwa isango kuphela, inaliti ngokuvamile ichezukela kwesokunxele. Kodwa-ke, uma izandla zombili zithinta i-D, i-S-pole ngayinye, futhi neminwe ithinta isango, kungenzeka ukuthi uqaphele ukuchezuka kwenaliti kwesokudla. Umsuka umsuka umzimba inani lezikhundla kanye resistors ku-MOSFET has a reference point effect, ukuze ungene endaweni yesimo saturation.