40. 如右圖所示,已知該電晶體截止電壓VGS(off) = - 5 V,直流閘源極電壓 VGS = - 4 V 時,ID = 0.35 mA,則 R1/R2值為何?
【用戶】朱冠亘
【年級】小六上
【評論內容】?
【用戶】李泰均
【年級】國一下
【評論內容】Vs = ID * 20K = 7VVGS = VG - VS = -4VVG = 3V = 18 * (R2/ (R1+R2) )(R2/ (R1+R2) ) = 1/6 , R1 = 5R2故R1/R2 = 5。