交流分析 R 10V 2kQ B 20kQ R R Rol R Re R (1+)b 15kQ v R 2kQ Rb (3)求输入电阻 26ml 26 The=rbb+(1+B 200+101 166Q TE(mA) 18 RFRb//rb/( e+(1+BRe8.2kQ2（3）求输入电阻 = + + = +  = k I mA mV r r E b e b b 1.66 1.8 26 200 101 ( ) 26 (1 ) '  交流分析 + – vs Rb1 b c Rc VCC vo1 Rs Re Rb2 Cb1 + 20k 15k 2k 2k 2k + + 10V vo2 e Ro2 Ro1 + – e Vi Rb1 rbe b I b Ic Rc + – Rs c I b Rb2 (1+)I b Rb Re Vo2 Vo1 + – Vs – + Ri=Rb1//Rb2//(rbe+(1+)Re=8.2k