Introduction to CMOS RF Integrated Circuits Design

Transcription

1 Introduction to CMO F Interated Circuit Dein III. Low Noie Aplifier Introduction to CMO F Interated Circuit Dein Fall 0, Prof. JianJun Zhou III-

2 Outline Fiure of erit Baic tructure Input and output atchin Noie (NF) ain (over the band) Linearity (IIP3, FD) tability Introduction to CMO F Interated Circuit Dein Fall 0, Prof. JianJun Zhou III-

3 Fiure of Merit (FOM) Frequency Noie Fiure Linearity (CP-dB, IIP3) Bandwidth and Q ain Power Conuption upply Voltae tability Introduction to CMO F Interated Circuit Dein Fall 0, Prof. JianJun Zhou III-3

4 Typical Value NF IIP3 CP-dB ain ~ db ~ 0 db ~ -0 db 5~ 0 db, < -0 db < - 30 db upply Voltae ~.-.8 V Current ~ 5 A Introduction to CMO F Interated Circuit Dein Fall 0, Prof. JianJun Zhou III-4

5 C tructure V out C u C db +C L V in Introduction to CMO F Interated Circuit Dein Fall 0, Prof. JianJun Zhou III-5

6 Doinant Pole The input cap i uually the doinant pole: V out C u C db +C L V in 0 ( Cin AV Cu ) 0 C in ( A V u) C in A V u Introduction to CMO F Interated Circuit Dein Fall 0, Prof. JianJun Zhou III-6

7 Doinant Pole For a voltae ain of L, at low freq., we have: 0 Cin AV u ( L) 0 Av L T u A If A v =0 and L / =,u=0. v )( u L T C in u 0 T 0 Introduction to CMO F Interated Circuit Dein Fall 0, Prof. JianJun Zhou III-7

8 Obervation For hih frequency operation hiher T i deirable hih hih current Le capacitance i deirable Lower ain reduce Miller capacitance? but we uually need a certain aount of ain. o what to do? (Think.cacode?) Introduction to CMO F Interated Circuit Dein Fall 0, Prof. JianJun Zhou III-8

9 Input Matchin-- --Why Provide ood Terination for Traniion Line fro Antenna (Antenna/F filter uually are deined with 50Ω terination, ae a the eaureent equipent) Maxiize Power Tranferred Conjuate atchin Preerve Characteritic of Duplexer Filter tability Connection lenth λ/4 hould be conidered a traniion line Introduction to CMO F Interated Circuit Dein Fall 0, Prof. JianJun Zhou III-9

10 Input Matchin - eitive Terination Extra Noie fro T => NF 3 db Input Noie ource i Attenuated => NF i deraded further Z in T Z in = T = 50 Introduction to CMO F Interated Circuit Dein Fall 0, Prof. JianJun Zhou III-0

11 Input Matchin - / Terination equire Lare Power to Achieve 50-Oh Matchin Unity Current ain => Current Noie becoe inificant and Liited evere Iolation Z in Z in = / = 50 Introduction to CMO F Interated Circuit Dein Fall 0, Prof. JianJun Zhou III-

12 Input Matchin - / Terination veq F 4kT BJT: Fin MO: Fin 3.5.8dB.7.dB Introduction to CMO F Interated Circuit Dein Fall 0, Prof. JianJun Zhou III-

13 Input Matchin-- --eitive hunt Feedback Added noie Broadband Aplification due to Feedback => More Power to educe Noie F Z in Z in = F /(+Av)= 50 Introduction to CMO F Interated Circuit Dein Fall 0, Prof. JianJun Zhou III-3

14 Input Matchin-- --Inductive Deeneration Ideal Inductor are Noiele => No Extra Noie Contribution More Flexibility in Dein and Optiization Z in L L Z in = 50 Introduction to CMO F Interated Circuit Dein Fall 0, Prof. JianJun Zhou III-4

15 Input Matchin-- --Inductive Deeneration Z in Z L Z C ( Z C ) Z L ( L L ) C C L T f ( L L ) C Introduction to CMO F Interated Circuit Dein Fall 0, Prof. JianJun Zhou III-5

16 Input Matchin-- --Inductive Deeneration Low-Q Inductor: elatively Broad Band all Dein Headroo for Matchin all Noie => Lare => all L => Lare L => L paraitic reitance contribute ore noie Inductor, in particular L, have been ipleented uin bondwire or off-chip Introduction to CMO F Interated Circuit Dein Fall 0, Prof. JianJun Zhou III-6

17 LNA - Perforance NF and ain of the LNA deterine NF total LNA i there to iprove the overall noie perforance (NF Mix >NF LNA ) Hih IIP3 of LNA i uually deired for reducin in-band IM ditortion Total IIP3 i uually deterined by Mixer and the followin block, not by LNA Matchin i optiized for overall inal perforance in the front-end Introduction to CMO F Interated Circuit Dein Fall 0, Prof. JianJun Zhou III-7

18 LNA - Noie Fiure i i n,d i n, d 4KT d 0f i 4KT C 5 d 0 c i i i * d i d Introduction to CMO F Interated Circuit Dein Fall 0, Prof. JianJun Zhou III-8

19 Introduction to CMO F Interated Circuit Dein Fall 0, Prof. JianJun Zhou III-9 LNA LNA - Noie Fiure Noie Fiure f KT i u u 4 n C c e i Y jb Y C C C jb Y f KT i 4 f KT e n n 4 n C u i e Y Y i NF ) / ( ) ( opt n C opt n Y Y NF c c n u opt opt opt jb jb Y /

20 LNA - Noie Fiure v i n,d The current ain of the MO Aplifier i iven by: i o v v ( ) j C jc v v ( ) j C ( ) jc Introduction to CMO F Interated Circuit Dein Fall 0, Prof. JianJun Zhou III-0

21 Introduction to CMO F Interated Circuit Dein Fall 0, Prof. JianJun Zhou III- LNA LNA - Noie Fiure Noie Fiure o v i Thi can be re-written a: ) ( T j The total noie i iven by: d T o i v v i, ) ( The noie fiure i iven by: d v i v v F

22 LNA - Noie Fiure ubtitution of the variou noie ource lead to: F ( ) ( ) ( T ) Aue >> F ( ) ( ) T It iportant to note that thi expreion contain both the channel noie and the ate induced noie. If we aue that = poly + /5, and the noie i independent fro the drain theral noie, we et a very ood approxiation to the actual noie without uin correlated noie ource. Introduction to CMO F Interated Circuit Dein Fall 0, Prof. JianJun Zhou III-

23 Introduction to CMO F Interated Circuit Dein Fall 0, Prof. JianJun Zhou III-3 LNA LNA - Noie Fiure Noie Fiure The optial value of 0 ) )( ( T F T ) )( ( T T opt ) ( ) ( ) )( (, ) ( ) ( in T F

24 LNA - Noie Fiure Let find,opt for a typical aplifier. ay f T = 75Hz, f = 5 Hz, and (γ/α)=. Alo uppoe that by proper layout poly i very all. The intrinic ate reitance i iven by: 0. poly Note that for V -V T = 00V, the required current i: Id ( V VT ) 40 00V 4A F, opt in f T f ( ) ( ) T ( ) dB Introduction to CMO F Interated Circuit Dein Fall 0, Prof. JianJun Zhou III-4

25 LNA - Noie Fiure for a iven circuit / bia ource adittance Y; there i an optiu adittance to Fin! the F Filter / Duplexer ipedance = 50Ω(Y= atchin i a ut!) the NF optiization i fixed), but by chanin the bia and W/L ratio circuit it i difficult/ipoible 50Ωinput atchin and Fin The noie i hiher at hiher frequencie Introduction to CMO F Interated Circuit Dein Fall 0, Prof. JianJun Zhou III-5

26 LNA - Noie Fiure L L Z in L L Introduction to CMO F Interated Circuit Dein Fall 0, Prof. JianJun Zhou III-6

27 LNA - Noie Fiure v i n,d It fairly eay to calculate the noie for the cae with inductive deeneration. iply oberve that the input enerator noie ee a ain of to the output. The drain noie, thouh, require a careful analyi. ince it flow partly into the ource of the device, it activate the of the tranitor which produce a correlated noie in hunt with drain noie. Introduction to CMO F Interated Circuit Dein Fall 0, Prof. JianJun Zhou III-7

28 LNA - Noie Fiure i n,d The above equivalent circuit how that the noie coponent flowin into the ource i iven by the current divider: v v i ( d ) jl jl jc jl jc Introduction to CMO F Interated Circuit Dein Fall 0, Prof. JianJun Zhou III-8

29 LNA - Noie Fiure At reonance: v v v jl ( v id ) i ) ( v L ( ) C d i d L C L C jc When atched, L T v i d L C v id L C ) i d Introduction to CMO F Interated Circuit Dein Fall 0, Prof. JianJun Zhou III-9

30 Introduction to CMO F Interated Circuit Dein Fall 0, Prof. JianJun Zhou III-30 LNA LNA - Noie Fiure Noie Fiure o we ee that only /4 of the drain noie flow into the output! The total output noie i therefore 4 ) (, d T o i v v i 4 d v i v v F T F 4 ) ( ) ( ) ( T F ) ( ) ( The inductive deeneration did not raie the noie! o the iniu noie fiure F in i the ae. The advantae i that the input ipedance i now real and proraable (ω T L ). By proper izin, it poible to obtain a noie and power atch.

31 LNA - Effective Either By hort-cut or By erie eonant Tank: Z C Z in Q in o Z C o T Introduction to CMO F Interated Circuit Dein Fall 0, Prof. JianJun Zhou III-3

32 Introduction to CMO F Interated Circuit Dein Fall 0, Prof. JianJun Zhou III-3 o T o T T D I I L L V V L L W W T D /,,, ae a C and Power are educed! LNA LNA - Effective Effective

33 LNA Linearity Conideration i d bv cv 3 V V i in in i V V Q V in in in C C 0 0 V Q V Q ) V Q i in b( in c( in ) 3 d V in L C I in I d 4 Q/ A, in IP3 3 c( Q/) 3 6 3cQ L Larer or aller Q larer IP3 larer power conuption or larer C Introduction to CMO F Interated Circuit Dein Fall 0, Prof. JianJun Zhou III-33

34 LNA Linearity Conideration Maxiize Q or V => NF Deradation For ae Power, Miniize Device ize For ae Device ize, Maxiize Power Maxiize upply Voltae Miniize ain Eploy Differential Topoloy Introduction to CMO F Interated Circuit Dein Fall 0, Prof. JianJun Zhou III-34

35 LNA Output Loadin all eitive Load => all ain Lare eitive Load => Proble with Bandwidth, Voltae Headroo and Linearity Inductor eonate Output Capacitance for Hih Frequency, Hih ain, and Narrow-Band Filterin Introduction to CMO F Interated Circuit Dein Fall 0, Prof. JianJun Zhou III-35

36 LNA Output Loadin For Low-Q Inductor, May Need Neative- Copenation to Achieve Hih and Tunable Q and ain Neative- Copenation Circuitry Derade NF, Linearity, and Power Introduction to CMO F Interated Circuit Dein Fall 0, Prof. JianJun Zhou III-36

37 LNA Output Matchin Network Drivin Off-Chip Filter Need Output Matchin: Preerve Filter Characteritic Need 50-Oh Buffer Conue Power and Derade Linearity LC eonant Loadin Can Alo Be Ued for Matchin Drivin On-Chip May NOT Need Matchin Introduction to CMO F Interated Circuit Dein Fall 0, Prof. JianJun Zhou III-37

38 LNA tability Criteria K Z Z A P in in P P o in,, Z Z P P in o o o L L Introduction to CMO F Interated Circuit Dein Fall 0, Prof. JianJun Zhou III-38

39 LNA Cacode Dein Increae evere Iolation => Iproved tability Increae Voltae ain Eliinate Input Miller Capacitance acrifice Voltae Headroo and Linearity L V B v o Z in L Introduction to CMO F Interated Circuit Dein Fall 0, Prof. JianJun Zhou III-39

40 Coparion Z in F(50 Oh) ain Typical NF (db) C/hunt eitor h 4 L 0 Coon ate / L 5 Feedback tae F L L ( L F ) 6 Inductor ource Deeneration L C ( Q in ) Q in L Introduction to CMO F Interated Circuit Dein Fall 0, Prof. JianJun Zhou III-40

41 LNA Differential Dein Inenitive to Paraitic Inductor eject Coon-Mode Noie (ubtrate, upply) Iproved Linearity and Dynaic ane Hiher NF for ae Power or ae NF for Doubled Power Larer Chip Area Antenna and Duplexer Filter Are inle-ended Need Balun to Convert inle-ended inal to Differential Introduction to CMO F Interated Circuit Dein Fall 0, Prof. JianJun Zhou III-4

42 Cacode With Inter-tae Matchin V B C a v o M Without L int, M i loaded by Z=/( +jωc ) Z in L L L int M L int provide inter-tae atchin (C a i for table reaon) The ain of firt tae i iproved The NF reduced Larer ilicon area Introduction to CMO F Interated Circuit Dein Fall 0, Prof. JianJun Zhou III-4

43 Low Voltae Operation v dd L V B No tacked tranitor. V B i ued to control the ain. Which will not affect input atchin. Z in L L 0 C 0 Introduction to CMO F Interated Circuit Dein Fall 0, Prof. JianJun Zhou III-43

44 Introduction to CMO F Interated Circuit Dein Fall 0, Prof. JianJun Zhou III-44