Momwe mungadziwire ngati MOSFET ndi yabwino kapena yoyipa?

Yachiwiri: kuwongolera moyenera mphamvu yamagetsi yamagawo a MOSFETMultimeter idzayimbidwa ku fayilo ya R × 100, cholembera chofiira mwachisawawa chikugwirizana ndi chubu cha phazi, cholembera chakuda chikugwirizana ndi chubu lina la phazi, kotero kuti phazi lachitatu likulendewera mlengalenga. Ngati mupeza kuti singano ili ndi kugwedezeka pang'ono, zimatsimikiziridwa kuti phazi lachitatu lachipata. Kuti muwone bwino kwambiri momwe zimachitikira, komanso kugwedezeka kwamagetsi pafupi kapena kukhudza kwachala komwe kukulendewera pamapazi amlengalenga, kungowona singano yopatuka kwakukulu, kutanthauza kuti, kuwonetsa kuti kupachikidwa pamapazi amlengalenga ndi chipata. , mapazi ena awiriwo anali gwero ndi kukhetsa.

Zifukwa Zosiyanitsira:

JFET athandizira kukana ndi kuposa 100MΩ, ndi transconductance ndi mkulu kwambiri, pamene chipata kutsogolo m'nyumba danga maginito n'zosavuta kwambiri maginito kukopa ntchito voteji deta chizindikiro pachipata, kuti chitoliro amakonda kukhala mpaka, kapena amachitira. kukhala on-off. Ngati mphamvu yamagetsi yamagetsi imawonjezedwa pachipata, chifukwa cholumikizira chachikulu chamagetsi ndi champhamvu, zomwe zili pamwambapa zikhala zofunika kwambiri. Ngati singano ya mita yomwe ili kumanzere kwapatuka kwakukulu, m'malo mwa chitolirocho imakhala ngati, kukulitsa kwa RDS, kukhetsa-gwero kwa IDS yochepetsedwa. M'malo mwake, singano ya mita kumanja kwa kupatuka kwakukulu, zomwe zikuwonetsa kuti chitolirocho chimakhala chozimitsa, RDS ↓, IDS ↑. Komabe, singano ya mita pamapeto pake yomwe imapatuka, iyenera kudalira mizati yabwino komanso yoyipa ya voteji yomwe idapangidwa (njira yabwino yamagetsi ogwirira ntchito kapena njira yosinthira mphamvu yamagetsi) ndi malo opangira chitoliro chachitsulo.
Zochenjeza:
(1) Kuyeseraku kukuwonetsa kuti manja onse akachotsedwa pamitengo ya D ndi S ndipo chipata chokha chimakhudzidwa, singanoyo nthawi zambiri imapatutsidwa kumanzere. Komabe, ngati manja onse awiri akhudza aliyense wa D, S-pole, ndi zala zikugwira pachipata, ndizotheka kuyang'ana kukhota kwa singano kumanja. Choyambitsa chake ndi gulu la malo angapo ndi zotsutsa pa MOSFET zimakhala ndi mfundo zowonetsera, kuti zilowe m'dera la saturation.