(交流)动态分析A.、R;、R.26(mV)计算rbe ~ 200(2)+(1+ β)IbeI,(mA)A, =-βR微变等效电路:Tei. Bi.R'= Rc I/ R,RsBIR; = Rbllrbe ~ rbeRURBU,RrbeR。= RcE,OEr:A工Aus =Rs+ri
动态分析(交流)——Au 、 Ri 、 Ro (mA) 26(mV ) 200( ) (1 ) E be I r + + β Ui i I b I c I Uo b βI ES RB rbe RC RL E B C + - + - + - RS 计算 rbe 微变等效电路: be L r R Au = − L C L R = R // R u Au R r r A + = S i i s 𝑹𝒐 = 𝑹𝑪 𝑹𝒊 = 𝑹𝑩//𝒓𝒃𝒆 ≈ 𝒓𝒃𝒆
5、有发射极电阻的放大电路(1加Re)静态分析:o+Ucco+UccIIcRBRBRRC2CH1BRR.uu;ReReCECes11Ucc -UBEQ点:Ic = βIBIg= Rs +(1+ β)ReUce = Ucc -IRe -IcRc ~ Ucc -Ic(Rc + Re)
RB RC C1 C2 CE RE RL + + +UCC ui uo + + – – RS eS + – B E CC B E B R (1 )R U U I + + − = C βIB Q点: I = CE CC E E C RC U = U − I R − I RB RC RE IB +UCC IC ( ) CC C RC RE U − I + 5、有发射极电阻的放大电路(1加RE) 静态分析:
动态分析:微变等效电路1Bβ1'beRERR.u.U.RB1E.0Reli.IβR'R。= RcUrbe +(1+ β)ReR; = RB1ll[rbe+(1+β) Re]
be E L r (1 β )R βR Au + + = − rbe RC RL E B C + - + - + - RS Ui i I b I c I Uo b β I ES e I R E RB1 动态分析: 微变等效电路 𝑹𝒐 = 𝑹𝑪 𝑹𝒊 = 𝑹𝑩𝟏// [𝒓𝒃𝒆+(1+𝜷) 𝑹𝑬]
6、有发射极电阻和电容的放大电路同2(2加Ce)静态分析o+Ucc.+UccI IcRB-RBSRcCIB人RsR1uU:RE.ReesY1Ucc-0BEQ点:Ic = βIBIB= Re +(1+ β)ReUce = Ucc -IRe -IcRc ~ Ucc - Ic(Rc + Re)
RB RC C1 C2 CE RE RL + + +UCC ui uo + + – – RS eS + – B E CC B E B R (1 )R U U I + + − = C βIB Q点: I = CE CC E E C RC U = U − I R − I RB RC RE IB +UCC IC ( ) CC C RC RE U − I + 6、有发射极电阻和电容的放大电路 (2加CE) 静态分析: + 同2
同1动态分析微变等效电路:A, =-βRi. Bi.I'beR' = Rc // R,BIRBRc Ru.1Ur'beR, = Rbllrbe ~ rbeER= Rc
动态分析: Ui i I b I c I Uo b βI ES RB rbe RC RL E B C + - + - + - RS 微变等效电路: be L r R Au = − L C L R = R // R 同1 𝑹𝒐 = 𝑹𝑪 𝑹𝒊 = 𝑹𝑩//𝒓𝒃𝒆 ≈ 𝒓𝒃𝒆