例6,3,1(2)放大电路的输入、输出电阻 bel= re2=5.45kQ2, rbe3 =262ke2, rbe4=rbes=2.8kQ2, rbe=725Q2 =200k2 6=100 +wee+10w Rd=2re1=10.9k92 aIko Rc=0.5lrbe+(1+6)2re7]=20M 3 Q Rn1=R2=14.3kg 5 R2=199Mg T 3.5ko rbe3+(1+ BIrbe4+(1+ BR4I 'RnR Ro2=R2=5.1ks 1.9kn Ra2=0.41kQ 5 +r +rce9/(R5+ be T,dRs +B6 D =N6 1+B R3=10.6M9 EE-l0V Thes+(1+ Rs +rces/[/be6+(1+ BRe
6 例6.3.1 （2）放大电路的输入、输出电阻 rbe1= rbe2=5.45k，rbe3 =262k ，rbe4= rbe5=2.8k，rbe6=725 rce =200k =100 Rid= Ric = Ro2= Ri2 =19.9M Ro1= = rbe3 + (1+ )[rbe4 +(1+ )R4 ] Ri3 =10.6M Ro3 0.41k 7 6 5 3 6 ce9 5 6 1 1 r R r r R R //( ) // be be 2rbe1 =10.9k 0.5[rbe1 +(1+ )2rce7 ] =20M R2=14.3k R3=5.1k = rbe5 + (1+ ){R5 + rce9 // [rbe6 +(1+ )R6 ]}
例631(3)放大电路的总增益 ⅴD·av2 A V3 i1 D2 c2 4 A VD -c2=2vn 2 VT2 +vee+10v R2强 B(R2∥R12)βR2=129 2 2 be e T 5 R12=199Mg>>R2 IB3ib3+(1+B3)ib3B,R3//Ri3 V2 R b3(/be3+(1+B)lrbe4 +(+B)R4I boko 3B4R3 2.6 12 T"0 R3=10.6Mg2 3 ≈ A=-335 2 VEE-I0V
7 例6.3.1 （3）放大电路的总增益 VD V2 V3 c4 o c2 c4 i1 i2 c2 V A A A v v v v v v v A = 129 ( // ) = be 2 be 2 i2 2r R 2r R R Ri2 =19.9M >> R2 VT2 i2 c2 i1 i2 c2 VD 2 1 = A 2v v v v v A { ( )[ ( ) ]} [ ( ) ] // be3 be4 4 3 i3 V2 i r 1 r 1 R i 1 i R R A b3 3 b3 3 b3 4 2.6 i2 3 R 3 4R AV 335 AV 3 1 Ri3 =10.6M