44如【圖十三】所示,JFET電路中;Cl = C2 = 0.02
,C3=20|
,汲_源極飽和電流 IDSS = 4mA,汲-源極夾止電壓VGS(off) = Vp= -4 V,求VGS偏壓為多少伏特? 
(A) -9 + 4√3
(B)3√3-8
(C) 3√3-7
(D) -8 + 4√3
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統計: A(6), B(10), C(9), D(58), E(0) #891845
統計: A(6), B(10), C(9), D(58), E(0) #891845
詳解 (共 3 筆)
#1670072
VG=0 VGS=-VS
ID=4[1-(VGS/VP)]^2=VS/RS
=>4*[1-(-VS)/(-4)]^2=VS/0.5
=>16[1-(VS/2)+(VS^2)/16=8VS
=>VS^2-16VS-256=0
得VS=8-4*根號3(8+4*根號3不合,因為其值為15V)
又VS=-VGS=-8+4*根號3
2
2
#1138054
這題有辦法解嗎 怎麼算都算不出來
1
0
#5338305
ID= 4 [1-(VGS / VP)]^2 = VS/ RS
4 * [1-(-VS)/(-4)]^2 = VS / 0.5
4 * [1- Vs/2 + Vs2/16 ] = 2Vs
4 - 2Vs + Vs2 /4 =2Vs
4 - 4Vs + Vs2 /4 =0
Vs2 - 16Vs + 16=0
Vs = ... 得解
0
0