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VCC=15VRb1=2.5k?RCRb2=10k?Rb2?&UiUoReRLRc=3k?RL=3k?Rb1VCC解：①β=50CbRb1U?UBEQUBEQ=0.6VUBQ?VCC?3VRe?BQ?1.2k?Rb1?Rb2IEQrbb’=300?IBQ?ICQ??0.04mA?40?AI=2mA②ICQ?IEQ?2mAEQUCEQ?VCC?ICQRc?IEQRe?6.6V26&??(Rc//RL)?77.8r?r?(1??)?963?③bebb?AuIEQrberRi?be?18.8?Ro?Rc?3k?1??习题2-18 P107C1C2习题2-19 P107解：(a)共基电路(b)共射电路(c)共集电路(d)共射电路(e)共射－共基电路可编辑范本

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习题2-20 P107Rd4iD/mA3VDD2105101520RguI+uO?iDuGS=3V2V1.5V1VuDS/VQ+-VGG-解：①直流负载线方程：uDS?VDD?iDRd?20?5.1iDUGSQ?2V,UDSQ?8.3V,IDQ?2.3mA?iDg??1.7mS②m?uGSRo?Rd?5.1k?③Au??gmRd??8.7VDD=20VVGG=2VRd=5.1k?Rg=10M?习题2-21 P108C1+&U-iR2Rg①Au= -gm(RD//RL) ?-22.5Ri= RG+ (R1//R2) ?20 M?Ro= RD=15 k?②不接CS 时，微变等效电路为Rd+VDDC2+RLR1Rs&Uo-CsVDD=30VRd=15k?Rs=1k?Rg=20M?R1=30k?R2=200k?RL=1M?gm=1.5mSGRgD?UgsR1R2S?gmUgsRsRdRL可编辑范本

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GRgD?UgsR1R2S?gmUgsRsRdRLVDD=30VRd=15k?Rs=1k?Rg=20M?R1=30k?R2=200k?RL=1M?gm=1.5mS&?U&?I&R?(1?gR)U&Uigsdsmsgs&??gU&Uomgs(Rd//RL)&Ugm(Rd//RL)o?Au?????9&U1?gRims习题2-22 P109RguIVGGRsIDuOVDDUGS(th)=2VIDO=2mAVDD=20VVGG=4VRs=4.7k?Rg=1M?UGSQ?VGG?IDQRs2?UGSQ?IDQ?0.27mAIDQ?IDO??1??U??GS(th)?2gm?IDOIDQ?0.735mSUGS(th)UGSQ?2.73V可编辑范本

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微变等效电路GSuI&gmUgsDRSuo&?gU&UomgsRs&?U&?U&?(1?gR)U&Uigsomsgs&UgmRso?Au???0.776&Ui1?gmRsUGS(th)=2VIDO=2mAVDD=20VVGG=4VRs=4.7k?Rg=1M?习题2-23 P109Rb1C1Rc1VT1VCC?UBEQ解：①设UBEQ1=UBEQ2=0.7，?IBQ1?RbICQ1??1IBQ1?2mA?0.04mARc2+VCCVT2Re2uIuO设IBQ2<