427对输出电阻的影响 2.电流负反馈 Ios=AX =A(xi-x=A(xi-blos) A X 1+4B Uo=AX RO=AXR B 则反馈放大器的输出电阻为: =(1+A,B)R31 ( ) ( ) os s s i f s i os I A X A X X A X BI 1 s i os s A X I A B (1 ) oo of s o os U R A B R I 则反馈放大器的输出电阻为: Uoo AsX Ro AsXiRo 4.2.7 对输出电阻的影响 2.电流负反馈