童诗白模拟电子技术基础第四版第六章

1、Rb2Rc+VccuiT+-+-uoC1+C2Rb1ReCeRLRbRc+VccuiT+_+_uoC1RL+_+_C2CEQQCiUIT0 u时，)(ECiIIT 0u时时，)(EBBEUUUEeEIRUBCII阻容耦合共射放大电路阻容耦合共射放大电路RbRc+VccuiT+_+_uoC1RL+_+_C2_阻容耦合共集放大电路阻容耦合共集放大电路RbRs+VccuiT+_+_uoC1RL+_+C2us+_Re具有射极电阻的共射电路具有射极电阻的共射电路Rb2Rc+VccuiT+-uoC1+C2Rb1ReRL 直接耦合两级放大电路直接耦合两级放大电路Rb2Rc1+VccuiT1+-+-uoRb1

2、Rc2T2Re2 直接耦合两级放大电路直接耦合两级放大电路Rb2Rc1+VccuiT1+-+-uoRb1Rc2T2Re2Rf AuOuIDZUZR1R2RUREFuO AuOuI-+A1R2-+A2uOR3R4uO1uIR1+R1R2R3R4uiu0+R1R2RLR3ui+u0Rf+ufIifiiX0XiXfX对地电压对地电压iiXX iXXi+uf+R1R2RLR3ui+u0Rf+duIifidi(a)(b)iuu d)(fiduuu Idii)(fIdiii +R1R2R3R4uiu0uO-+AuIR2R1-+AuIuOR2R1C-+AuIuOR2R1C；则为电压反馈则为电压反馈若若,0

3、x ,0u f0 令。则则为为电电流流反反馈馈若若,0 x ,0u f0 +R1R2RLR3ui+u0Rf(a)(b)图图（a）中中 0u0 uf0 ，则图图（b）中中 0i0 uf0 ，则+uffio41341fuRRRRRu/Ioof33fIRRRIIo+R1R2R3R4uiu0-+A1R2-+A2uOR3R4uO1uIR1ud+-uf+iifR1+VCCuiT1+-C1R2R3+-uoC2T2R4R5R6C3+uf+VCCfIT1+-C1Rc1Re1+-C3T2Re2Rc2RfC2RRs+-usuIuOoIiI6262负反馈放大电路的四种基本组态负反馈放大电路的四种基本组态-+AuiuO

4、R2R1RLuduf-+usRs+-0u0RLR+-0u当当RL0L0L0uRRRu0211fuRRRu )(fiduuu，越小，越小，sisuuRu0uf 0u反馈越明显；反馈越明显；+R1RsRLR3us+u0RfridIiIfI00I0RLR0I0L000IRRRI当当RL0f33fIRRRI )(fidIII，时时 当当0R s 一定，反馈越明显;一定，反馈越明显;iI。越大，反馈越明显越大，反馈越明显sRdIfI0I 0IidsdruI -+R2RfuoR1Rc+VccuiT-+R2RfuoR1Rc+VccuiT-+R2RfuoR1Rc+VccuiTRe-+R2RfuoR1Rc+Vc

5、cuiTRe6363负反馈放大电路方块图及一般表达式负反馈放大电路方块图及一般表达式iXiXfXoXAF fiiXXX ioXXA ofXXF ifXXFA iofXXAFAA1iiiXFAXXA fioXXXF1AFAAf1fAAFFAAAf1，时时 当当 1 FA1 A Af，时时 当当0 FA1 。时时，即即0X0 X 0i反反馈馈深深度度 FA1 1 FA1 当当FA1AAf ioXXA iofXXAA Af负反馈负反馈，时时 当当 1 FA1 正反馈正反馈 Af,自激振荡自激振荡F1FAAiUfUiUoUuuAuuF+-+-+-RLoIiUfUiUoUiuAuiF+-+-+-RLiI

6、fIiIoUuiAiuF+-RLoIiIfIiIoUiiAiiF+-RL F1Af iofXXA ofXXF当当10|1 |FA fofXXF1A fiXX fiUU fiIIufuIR1T1uo-R4+VCCT2I-VCCR2R3T3+-+R5422ofuuRRRUUF 2411RRFUUAuuiouf ufA11101001fiUUo422fURRRU ufAfARb1+VCCT1+-C1Rc1Re1+-C2T2Rc2Re2RfC3iUoUR oU iU fA ufAf1e1eofuuRRRUUF iouffUUAAfiUUuf1efuuRR1F1 ofeefURRRU11usfAfA o

7、f2e2efIRRRIf2e2eofiiRRRIIF 2efiiioiifRR1F1IIA （2） sousfUUAus+VCCT1+-C1Rc1Re1+-C3T2Re2Rc2RfC2RRs+-uIuOoIiIfIfiIIssiRUILc2ooRRIU/sL2c2efRR/RRR1 ufAuf-+AuiuOR2R1RLuD+-+VCCR3iO o3213RIRRRRI11RfRIU1 32131ofuiRRRRRIUF foioufUUUUA LooRUIfiUU1o3213RIRRRR L31321RRRRRR 285210210010 AFAAf12fAF1AFAF1dAdA)(1AdAA

8、F11AdAff 2AF11)( dAAF11dA2f)( AdA AdAff 量量闭环放大倍数相对变化闭环放大倍数相对变化 AdAff量量开环放大倍数相对变化开环放大倍数相对变化 AdAiiiIURiiifIUR iUfUiUoXAF+-+-+RiRifRbRif iifRAF1R ibifbiRAF1/RR/RR iUfUiUoXAF+-+-+串联负反馈电路的方块图串联负反馈电路的方块图RiRifiI iiIUFA1 iiiIUFAU iRFA1 ifiIUU iIfIiIiUAF+-Ri并联负反馈电路的方块图并联负反馈电路的方块图oXRifiiiIUR iiifIUR iiIUFA11

9、iiiIFAIU fiiIIU FA1Ri 电压负反馈电路的方块图电压负反馈电路的方块图0Xi ofUFX fiXXoUAF+-Ro oUFA+-+-oIooofIURooooRUFAUI FA1RIURoooofooRUFA1 0iXofIFXfiXXoUAF+-RooIFA+-oIRofooofIUR ooooIFARUI FA1RUIooooooofRFA1IUR ooRFA1U HmHffj1AA FA1AAHHHfHmmmfFA1fj1FA1A HmmHfffjFA1AA HmHffFA1f mA Fffj1A1ffj1AHmHmHfmfffj1A FA1ffmLLfHLHbwfff

10、f HfLfHfbwfffff AFXiXoXf0tXi0tXf0tXiiXiXfXoXAF0tXo0tXi0tXiuIRc1T1uo-+VCCT2Re1b1T3+Re3Rc2Rb1+-Rc3c1e1c2e2c3e3uIRc1T1uo-Rf+VCCT2I-VCC+Rb2Rc3T3+Re3Rc2- 与、与、与、与、20ioUUAuRfof11fuRRRu (2)fiuu foiouuuuuA 1f1RRR 20RR11f190KRf- u f +uiuoR2R1Rf20K2.2K2K2K5.1K+uiuoR2R1Rf1K10K0.9KR3RL+uiuoR11.2K2KR3R2+3K+uiuo15KRfRL+5.1Kui20UUAiou +uiuoR2R1Rf20K2.2K2K2K5.1K+uiuoR2R1Rf1K10K0.9KR3RL+uiuoR11.2K2KR3R2+3K+uiuo15KRfRL+5.1KufufIifiIifi201RuRui