北大微电子:模拟集成电路原理 带源极负反馈的共源级 D g 1+mrS R =R M out P own n≈gm11R R ∴Rm=RpRm≈RD(Rm>Rp) R s (gmRs >>1) 1+8mR北大微电子：模拟集成电路原理 带源极负反馈的共源级 R g G m m 1 + = Rdown Rup R g r R R R g R up D 1 m S ≈ = + down g R R R R R (R R ) R g r R D out up down D down up down m o S || 1 1 ∴ = ≈ >> ≈ (g R ) R R R g R g A G R m S S D D m S m v m out 1 1 0 ≈ − >> + = − ≈ −