基本放大电路分类和应用1课件.ppt

1、1本章要求本章要求Aut uiuit uououAuat+UCCRCC1C2TuiRB+UCCRCC1C2TRB+UCCRCC1C2TRB+UCCRCC1C2TRB 13由于电源的存由于电源的存在在IB 0IC 0IBICIE=IB+ICui=0时时+_RB+UCCRCC1C2T14IBIC(IC,UCE)(IB,UBE)UBEUCERB+UCCRCC1C2T15(IB,UBE)和和(IC,UCE)分别对应于输入输出特性曲线上的一分别对应于输入输出特性曲线上的一个点称为静态工作点。个点称为静态工作点。IBUBEQIBUBEICUCEQUCEIC16IBUBEQICUCEuCE怎么变化怎么变化假

2、设假设uBE有一微小的变化有一微小的变化uit（毫伏量级）（毫伏量级）（微安量级）（微安量级）（毫安量级）（毫安量级）ibtictibtUBEIBUCEIC17sinimBEBEiBBbCCcCECEceoceuUtuUuiIiiIiuUuuu+UCCRBRCC1C2T+ui+uo+uBEuCEiCiBiE18UBEIB无输入信号无输入信号(ui=0)时时:uo=0uBE=UBEuCE=UCE？uCE=UCC iC RC uo 0uBE=UBE+uiuCE=UCE+uoIC+UCCRBRCC1C2T+ui+uo+uBEuCEiCiBiEuBEtOiBtOiCtOuCEtOuitOUCEuotO

3、实现放大的条件实现放大的条件1.晶体管必须偏置在放大区。发射结正偏，集电结反偏。2.正确设置静态工作点，使整个波形处于放大区。3.输入回路将变化的电压转化成变化的基极电流。4.输出回路将变化的集电极电流转化成变化的集电极电压，经电容滤波只输出交流信号。如何判断一个电路是否能实现放大？如何判断一个电路是否能实现放大？3.晶体管必须偏置在放大区。发射结正偏，集电结反晶体管必须偏置在放大区。发射结正偏，集电结反偏。偏。4.正确设置静态工作点，使整个波形处于放大区。正确设置静态工作点，使整个波形处于放大区。如果已给定电路的参数，则计算静态工作点来判断；如果如果已给定电路的参数，则计算静态工作点来判断；

4、如果未给定电路的参数，则根据电路结构确定未给定电路的参数，则根据电路结构确定。1.信号能否输入到放大电路中。信号能否输入到放大电路中。2.信号能否输出。信号能否输出。与实现放大的条件相对应，判断的过程如下：与实现放大的条件相对应，判断的过程如下：RB+UCCRCC1C2T直流通路直流通路RB+UCCRC+短路短路短路短路置零置零RB+UCCRCC1C2TRBRCRLuiuo+ui=0时时IBICRB+UCCRCC1C2T+ICUBEUCERB+UCCRCC1C2T+IBUBEQIBUBEICUCEQUCEICIBUBECCBEBBUUIR CCCCBB0.6UURR ICUCECBII ICU

5、CECCCURQIBRB+UCCRCICUCECCBEBBUUIR QCCCURCCBB120.04mA40 A300UIR CBB37.5 0.041.5mAIIICECCCC121.5 46 VUUI R ouiUAU iiiUrI oooUrI iBuBE uBE iBbeBEbeBbuurii beE26(mV)200()(1)(mA)rI iCuCECCcBb()iIiIi BbIicbii iC uCEubeibuceicubeuceicrbe ibibbce等效等效cbeuirbe ibibiiicuoRBRCRLRBRCRLuiuobiciiibibeUI r coLbLUI

6、RI R oLubeiRUArU LCL/RRR rbeRBRCRLiU iIbIcIoU bI Bbe/Rr ber iiiUrI iU iIbIcIoU bI ooCoUrRIoUrbeRBRCiIbIcIbI 00oIIB()UBEQuitIC(mA)UCEictucetA RB+UCCRCC1C2uituCuotuiiCuCuoiBiBttiCtibTUBE ICEOQCCBEBBUUIR Q I1I2IBRB1+UCCRCTRB2RE+I1I2IBRB1+UCCRCTRB2RE2BII CC12B1B2UIIRR B2B2VI R B2CCB1B2RURR BEBEBEEUVVVI

7、R BBEBCEEEVUVIIRR CECCCEEUEIRIR CBII I1I2IBRB1+UCCRCTRB2REBCEVIR I1I2IBRB1+UCCRCTRB2REB2BCCB1B23VRVURR E2.4mAI CE4.8VU+rbeRCRLoU iU iI bI cI bI RBiBbebe|rRrr oCrR LubeRAr ouiUAU oussUAU 放放大大电电路路oU iU sU iiSSirUURr iusuSirAARr oussUAU +CCBEBBE(1)UUIRR EB(1)II CECCEEUUI R+rbeiU bI RERLRBoU cI bI iI eo

8、LUI R LEL/RRR bL1I R （）beibeLUI rI R bbbeL(1)I rI R bLubbbeL(1)(1)I RAI rI R LbeL1(1)RrR （）rbeiU bI RERLRBoU cI bI iI beL(1),rR u1A ，LubeL1(1)RArR （）ibRBIIIiiBbeL/(1)rUIRrR RBiBIUR ibbeL(1)UIrR rbeiU bI RERLRBoU cI bI iI robI iI cI bI SU bI cI bI iI eI U I bbeIIII besbesEUUUrRrRR ssB:/RRR 设设oUrI bes

9、E111/()rRR besE/1rRR besE1rRR beso1rRr oUrI besE/1rRR +CCBEBBE(1)UUIRR EB(1)1.01mAII beE26(mV)200()(1)(mA)200101 26/1.012.8krI +LubeL1(1)RArR （）iBbeL/(1)rRrR 570/2.8(1100)2.8 190k beSoE/1rRrR 101 2.80.992.8101 2.8 2.805.6/101 28 rbeiU bI RERLRBoU cI bI iI iusuiSrAArR 1900.990.9851901 iBbeL/(1)rRrR 1

10、90k beSoE/1rRrR 2.8570/15.6/101 38 rbeiU bI RERLRBoU cI bI iI ubeL1(1)LRArR （）u101(5.6/1)0.9672.9101(5.6/1)A u101 5.60.9952.9101 5.6A G2GDDG1G2RVURR SSSSDVR IR I GSGSUVV ooumLigsUUAg RUU oLdLmgsUR IR g U 。iGG1G2(/)rRRR oDrR +UCCRS1M(+24V)R120k27kC2C3R3R2RLRE282k43k10k8k10kC1RC2T1RE1CET2SUoUiUo1i2UU

11、o1U i2U+UCCRS1M(+24V)R120k27kC2C3R3R2RLRE282k43k10k8k10kC1RC2T1RE1CET2SU oU iU rirooo1usus1u2si2soUUUAAAUUU ri2+UCCRS1M(+24V)R120k27kC2C3R3R2RLRE282k43k10k8k10kC1RC2T1RE1CET2SU oU iUSU iU be1rbe2rb1i1bi b2ib2i 0U iri2rorri2+UCCRS1M(+24V)R120k27kC2C3R3R2RLRE282k43k10k8k10kC1RC2T1RE1CET2SUoUiUSU iU be

12、1rbe2rb1i1bi b2ib2i 0U iri2rorius1u1isrAArR 1L1u1be11L1(1)51 1.70.968(1)2.951 1.7RArR i1us1u1i1S820.9680.7788220rAArR SU iU be1rbe2rb1i1bi b2ib2i 0U iri2ror2L2u2be250(10/10)1471.7RAr usus1u2147 0.778114.4AAA SU iU be1rbe2rb1i1bi b2ib2i 0U iri2ror+UCCuoRC2T2R2RE2uot0+UCCuoRC2T2R2RE2uoui1+UCCRCT1RBRCT

13、2RBui2REUEEuoui1+UCCRCT1RBRCT2RBui2REUEE i1i2d2uuu i1i2c2uuu dCMRRcAKA CMRRK ce3ce3c3UrIUCE3IC3Q rce3 1M T3:放大区放大区恒流源恒流源IB3Uce3uCEiC+VCC-EERCRCRRRET1T2uoui1ui2RPRB1RB2RE3T3+VCC-UEE+UCCuouiRCT1RRCR+T2-UEE+UCCuouiRCT1RRCR+T2-UEEbeLCd1drR/2)/R(RAA)r2(RRbeidC02RR beLCd1drR)/R(R21A21A)r2(RRbeidC0RR+UCCuo

14、uiRCT1RRCR+T2-UEEbeLCd1drR/2)/R(RAA)r2(RRbeidC02RR+UCCuouiRCT1RRCR+T2-UEE2u2uuuii2i1ic2uuuiid2id10uuui2ii1omE100%PP SCEURCSCE0.5IUR omSC0.5UU 较较小小SCA,2UU SCC2UU SCi2Uu 交越失真交越失真iSC/2uU iSC/2uU 0.5USCuitLSCoSCoRUIUU22maxmax、LSCoooRUIUP8222maxmaxmaxLSCavSCERUIUP 22)(sin2210ttdRUILSCav%5.784maxEoPPLSCoSCoRUIUUmaxmaxLSCLSCSCoRURUUP21222max 01)(sin21LSCLSCavRUttdRUILCCavavRUII12LSCLSCSCEERURUUPP 21222%5.784max EoPPuiuououo ttttR1D1D2R2