Source google image: https://www.researchgate.net/profile/Romain_Grezaud/publication/281047258/figure/fig26/AS:643560391073804@1530448162562/Schema-electrique-equivalent-et-idealise-dun-transistor-a-effet-de-champ-et-de-son.png
Schema equivalent electrique
Source google image: https://www.researchgate.net/profile/Romain_Grezaud/publication/281047258/figure/fig26/AS:643560391073804@1530448162562/Schema-electrique-equivalent-et-idealise-dun-transistor-a-effet-de-champ-et-de-son.png