场效应管放大电路

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2 3 ???? Ku=-gm(Rds//Rd) Ku=-gmRb(?±Rds>>Rd) Rt=Rg//Rgs=Rg RO=Rg Ku=-gm(Rds//Rd) Ku=-gmRd(?±Rds>>Rd) Rt=Rg+R1//R2=Rg Ro=Rd Ku=gmRs(1+gmRs) Rt=Rg+(R1//R2)=Rg Ro=Rds/(1+gmRds)=1/gm
????·??? ×??ú???? ?ò????Us=RgIb?°Ug=0 ?ù????Ugs=-RsIo ×??ú????Us=IdRs ????????Ug=EdRp ?ù????Ugs=EdRp-IdRs ·?????????Rp=R2/R1+R2 ????±??à?? ?¨1???????±?÷????????·???????Uds=Ed-Id(Rd+Rs)=15-3.2Id ??ID=0???òUDS=15·ü?????á×?±ê??±ê??N????????UDS=0????ID=4.7??°?????×?×?±ê??±ê??M??????M??
???????±?????òMN?????±?÷???????? ?¨2?????¤???????¨×????????????ù???????????÷???????????ú????????×?±ê????????????B×ó±??ù????ID=f(UGS)?ú???????¤???????? ?¨3???¨???¤??????×?±ê????×÷Tga=1/Rs???¤?????·?????????ü???¤???????à????Q??????Q??×÷?á?á???????????¤?????????à????Q???????????¤×÷??Q??Q????????IDQ=2.5??°???UGSQ=-3·ü??UDSG=7·ü??±í1????????·¨?????à???? ???????§???··???·¨ ???§????????±??????·???????????????§????·??ó???·???????§???·????????×???????±í?????ù???????§???·?ó????·??ó±????°????????????×è??·?·¨???§???????·?à????