hapter 0 Tranitor amplifier dein 0. tability conideration unconditionally table conditionally table tability factor ource tability circle load tability circle 0. mplifier dein for maximum ain unilateral cae bilateral cae imultaneouly conjuate match unilateral fiure of merit 0.3 ontant ain circle unilateral cae bilateral cae 0.4 ontant noie fiure circle 0.5 Broadband amplifier neative feedback amplifier balanced amplifier travelin wave amplifier 0.6 mall inal equivalent circuit model of tranitor BJT MEFET 0.7 D bia circuit for tranitor
0. tability conideration Baic. Unconditionally table for all in out k. onditionally table: there exit ome and uch that one or both of thee condition violated.
Dicuion. tability circle out in ( - plane with in tability circle ( - plane with in tability circle r r load r r load
. If =0in= the center of mith chart repreent a table point if < =0out= the center of mith chart repreent a table point if <
4. Ex.0. tranitor ha =0.894-60.6 =0.0 6.4 =3.3.6 =0.78-7.6at Hz.3646.7 r.3646.7 r 0.6964 0.5 0. k 0.607
0. mplifier dein for maximum ain Baic.Unilateral cae: =0 tability condition: << maximum ain: = = unilateral tranducer ain TU TU max
. Bilateral cae (imultaneouly conjuate match out in o in 4 4 k a ain table maximum : ( match conjuate uly imultaneo output and input B B B B B B K K K if M M M TMax T ut
3. Unilateral fiure of merit ( U U ( T U ( U ( Dicuion. inear amplifier dein procedure ( if < K> ue input and output imultaneouly conjuate matche for Tmax ( if K< plot ource and load tability circle to ee if input and output imultaneouly conjuate matche poible otherwie elect the proper and for ain or noie fiure conideration (to be dicued in the followin ection.
. Ex.0. tranitor ha (Zo=50 =0.606-55 =0 =680 =0.48-0at Hz dein an amplifier to ive TUmax. 0.606 TU max.58 36.3 73.9 8.69dB : y=j.7 or z=-j0.45 : z=j0. 3: z=-j.38 or y=j0.48 4: y=-j0.6 0.60655 0.48 0.480 0.606 6 0.48 # "!
3. Ex.0. tranitor ha (Zo=50 =0.64-67.4 =0.046 65 =.873.4 =0.76-83at 6Hz dein an amplifier to ive tmax < K=.96> in out TMax M M B ( K K B B B 4 4 8.78 4.58dB 0.8673 67.4 0.9084.48 % $& %$
:M=0.867369.76 : y=-j.7 3: M=0.9084.48 4: z=j3.4 ' ' ('
4. Ex.0.4 tranitor : =0.4550 =0.0-0 =.050 =0.4-0tranitor B: =0.64-7.3 =0.0576.3 =.0588.5 =0.57-95.7compare their U U ( ( U ( U T 0.476dB U 0.8948dB T ( U T U B U U B 0.038dB 0.9976dB 0.0055 0.085 0.989 0.838 T U T U B.0055.58 - +
.0 /. 0.3 ontant ain circle Baic. Unilateral cae (=0 max max max max 0 ( ( ( ain circle in contant ( ( ( ain circle in contant d d plane d d plane TU
6 35 43. Bilateral cae (0 ( Unconditionally table cae ue or max max max ( ( ( ( in circle ain contant T im im K K K K K c c c plane
: 79 87 max max max ( ( ( ( ain circle in contant T out out K K K K K c c plane
( otentially untable cae ue to plot contant ain circle in -plane and plot load tability circle properly elect calculate = in ue to plot contant ain circle in -plane and plot ource tability circle properly elect calculate = out Dicuion. Ex. 0.5 MEFET with -parameter (Zo=50 3Hz 0.8-90.800 0 0.66-50 4Hz 0.75-0.580 0 0.6-70 5Hz 0.7-40.360 0 0.68-85 plot contant ain circle @4Hz for =0 db and = 3dB dein an amplifier of db ain @ TU 0 4 Hz max 6.5 7.96 db TU.8 max 0 3.59 3.59 db 7.96 max.9 3.47 db.565.9 db > ;= <;
B? @? choe TU(4Hz db=db+8db+db to dein the circuit TU(3Hz=7.3TU(5Hz=6.96dB 0.44 0.303 70 0.64 70 0.5 0.64 0.8064 0.6 0.94 0.66 0 0.67 0 0.706 0.69 0.785.58 3 d db db d db db
. Ex. 0.6 a FET with -parameter (Zo=50 Hz =.7-0 =4 50 =0 =0.6-80 ( calculate Zin plot untable reion in -plane ( plot contant ain circle for =3 5dB (3 find Z for =3dB with maximum deree of table determine Z to ive maximum then dein the amplifier (4 calculate TU (.7 0 in 4.5 to be untable Zin Zin Z0 Z0 Zin 4.5 j3 F E D
J I H ( db j Z For j Z TU MX 7 50.56 4.56 5.5 7 80 0.6 : elect maximum 5 50 76 0.4 : poible maximum a ive to for Z elect (3 0.698 0.74 0 0.4 0 0.45 8.3 3.3 3 3.6 5 d db db
3. Ex. 0.7 a FET with -parameter (Zo=50 6Hz =0.64-7.3 =.0588.5 =0.0576.3=0.57-95.7dein an amplifier to ive =9dB K.5 0.3 Max ( K K.38dB 9dB contant ain circle in plane c p p c p 0.504 p 0.43 elect : 0.3650 in 0.63 75.6 : 0.6375.6 NM K
4. Ex. 0.8 a FET with -parameter (Zo=50 8Hz =0.5-80 =.570 =0.0830 =0.8-00dein an amplifier to ive =0dB ource tability circle.6770.6 r 0.998 K 0399. 0.8 load tability circle.797 r 0.3388 c p 0dB contant ain circle in plane 0.5797. elect : p 0.4733 0.97 in c 0.5 79.3 : p p 0.579.3 O Q O
5. Ex. 0.9 BJT with -parameter (Zo=50 750MHz =0.77-59 =.9 64 =0.07893 =0.848-3dein an amplifier to ive Tmax.035 0.34 imultaneouly conjuate match M = 0.79835? M = 0.9533.85 6. Ex. 0.0 ue the BJT in Ex.0.9 dein an amplifier to ive =0dB determine for max c p 0dB contant ain circle in 0.7833.8 elect : : MX 0.5634 0.345556.45.8dB 0.4 0.79835 p 0.9533.84 M in plane 0.3455 56.4 M c p p V VU T
0.4 ontant noie fiure circle Baic amplifier port - two a For F N F min min F 4 Y F / Z min contant noie fiure circle Y noie parameter : F opt n Y opt n opt 0 F min n 4 Z equivalent opt 0 n ( noie reitance of : noie fiure parameter NF NF opt opt tranito r NF opt N NF N ( N N N opt [ ZY XW
Dicuion. Ex. 0. BJT with -parameter (Zo=50 Hz =0.707-55 =5 80 =0 =0.5-0 Fmin=3dB n=4 opt= 0.4580dein an amplifier to ive T=6dB F<3.5dB F TUMX TU elect 3 3.98.3 8.9 db. db d 0.56 50 6 db 0.78 db d 0.46 0 3.5dB 0.3658 80 0.3953 NF B : D : NF 0.345 0.58 `_^]\
. Ex. 0. a FET with -parameter (Zo=50 4Hz =0.6-60 =.98 =0.056 =0.5-60 Fmin=.6dB n=0 opt= =0.6 00( aume =0 dein an amplifier to ive TUmax F<dB ( repeat for 0 K.778 0.373 U TUMax elect :.938 5.57.5 8.76dB 0.560 0.0594 0.5dB 0.59dB ( F db NF 0.5600 NF 0.45.5dB d 0.5660 0. elect :.7 db d 0.58660 0.5 T TU e dc ba
(ue 8dB elect contant ain circle in c 0.5764.7 0.53590 out plane 0.34 c 0.504 67.8 0.50467.8 3. ow noie amplifier dein procedure: if unconditionally table ue contant ain circle and contant noie fiure circle to determine and = out. if potentially untable conider ource and load tability circle in addition. j ih f
p Hz =0.6-30 =7. 86 =0.03935 =0.5-38 Fmin=.3dB n=8 opt= =0.0649 dein an amplifier to ive 6dB power ain F<.5dB ource tability circle.747 r 0.8566 K 0.7667 0.89 load tability circle.650.8 r.96 c a F elect B: 6dB 0.3547.5 out D : contant ain circle in plane 0.034640 0.30 0.469 36.45 NF 0.46936.45 a 0.673 NF 0.65 c a a o nm lk
u t rq 0.5 Broadband amplifier Baic. Neative feedback amplifier ' ' ' ( ' ( 0 0 0 0 0 0 0 0 0 0 0 c c c c c V v v i V f f f f f f j fc f j v V V
. Balanced amplifier {hybrid and amplifier ain. z yx wv
. Travelin wave amplifier (ditributed amplifier TEM line extreme wide operation bandwidth } ~ }
0.6 mall-inal equivalent circuit model of tranitor Baic. BJT ƒ
. MEFET ate f ate power ˆ
Ž 0.7 D bia circuit for tranitor Dicuion. eitive bia with voltae feedback for BJT Vcc ci Ic I I V E cc E to have I I Vcc VBE B c E E E V BE I B I B B V I BE B c le enitive to chane in V BE Œ Š
. Bia circuit with emitter bypaed reitor for BJT V V Th V V TH th th I E th th to have I V E V I B B V E in V cc VBE th BE V V ce BE E I TH E E th 0% V th ( le enitive to chane in V uually Vth 5% ~ lim ited output win cc E I BE E V BE
3. Unipolar bia circuit for MEFET