Ch. 9Ch. 9 FET Amplifiers and Sihi i iSwitching...
Transcript of Ch. 9Ch. 9 FET Amplifiers and Sihi i iSwitching...
![Page 1: Ch. 9Ch. 9 FET Amplifiers and Sihi i iSwitching circuitselearning.kocw.net/contents4/document/lec/2013/Hanky… · · 2013-08-30Yun SeopYu 동작 JFET 증폭기 - RG: 0V d0V dc로](https://reader034.fdocument.pub/reader034/viewer/2022042502/5aee4a6b7f8b9ac57a8bc207/html5/thumbnails/1.jpg)
Ch. 9Ch. 9 FET Amplifiers and S i hi i iSwitching circuits
![Page 2: Ch. 9Ch. 9 FET Amplifiers and Sihi i iSwitching circuitselearning.kocw.net/contents4/document/lec/2013/Hanky… · · 2013-08-30Yun SeopYu 동작 JFET 증폭기 - RG: 0V d0V dc로](https://reader034.fdocument.pub/reader034/viewer/2022042502/5aee4a6b7f8b9ac57a8bc207/html5/thumbnails/2.jpg)
Yun SeopYu동작
JFET 증폭기
R 0V d 로 VG유지- RG: 0V dc로 VG유지ac 신호의 부하영향 차단
180 위상차 (V 와 V )-180 위상차 (VGS와 VDS)-바이어스 전압: Rs 양단의 전압강하에 의해서
![Page 3: Ch. 9Ch. 9 FET Amplifiers and Sihi i iSwitching circuitselearning.kocw.net/contents4/document/lec/2013/Hanky… · · 2013-08-30Yun SeopYu 동작 JFET 증폭기 - RG: 0V d0V dc로](https://reader034.fdocument.pub/reader034/viewer/2022042502/5aee4a6b7f8b9ac57a8bc207/html5/thumbnails/3.jpg)
Yun SeopYu동작
JFET 증폭기 그래프 해석ID V 가 Q점에서 음의 값으로D
IDSS
I
-VGS가 Q점에서 음의 값으로변하면 Id 감소- VGS가 Q점에서 양의 값으로변하면 I 증가
Q IDQ
Id 변하면 Id 증가MOSFET도 비슷하다.
VGS 2⎞⎛
VGS(off)
V
Vgs )(
1 ⎟⎟⎠
⎞⎜⎜⎝
⎛−=
offGS
GSDSSD V
VII
VGSQ
Signal operation with n-channel JFET
⎠⎝
n channel JFET
![Page 4: Ch. 9Ch. 9 FET Amplifiers and Sihi i iSwitching circuitselearning.kocw.net/contents4/document/lec/2013/Hanky… · · 2013-08-30Yun SeopYu 동작 JFET 증폭기 - RG: 0V d0V dc로](https://reader034.fdocument.pub/reader034/viewer/2022042502/5aee4a6b7f8b9ac57a8bc207/html5/thumbnails/4.jpg)
Yun SeopYu동작
JFET 증폭기 그래프 해석VDS = VD-VS = VDD-ID(RD+RS)ID = -VDS/(RD+RS)+ VDD/(RD+RS)I
부하선
D DS D S DD D S
부하선y절편: VDS= 0 ID= VDD/(RD+RS)x절편: ID= 0 VDS = VDD
ID
IdVgs
부하선
VIDQ QVgs
V ↑ I ↑ V ↓
VGSQDQ Q
Vds
VGS ↑ ID ↑ VDS ↓VGS ↓ ID ↓ VDS ↑VDSQ0 VDS
ds
n-channeloperation
![Page 5: Ch. 9Ch. 9 FET Amplifiers and Sihi i iSwitching circuitselearning.kocw.net/contents4/document/lec/2013/Hanky… · · 2013-08-30Yun SeopYu 동작 JFET 증폭기 - RG: 0V d0V dc로](https://reader034.fdocument.pub/reader034/viewer/2022042502/5aee4a6b7f8b9ac57a8bc207/html5/thumbnails/5.jpg)
Yun SeopYu동작
D-MOSFET 증폭기 그래프 해석
ID
enhancement
Id
Q IDQ
VGS
V
depletion
VGS(off)
VGSQ
Vgs
VGSQ
![Page 6: Ch. 9Ch. 9 FET Amplifiers and Sihi i iSwitching circuitselearning.kocw.net/contents4/document/lec/2013/Hanky… · · 2013-08-30Yun SeopYu 동작 JFET 증폭기 - RG: 0V d0V dc로](https://reader034.fdocument.pub/reader034/viewer/2022042502/5aee4a6b7f8b9ac57a8bc207/html5/thumbnails/6.jpg)
Yun SeopYu동작
E-MOSFET 증폭기 그래프 해석
ID
Id
QIDQ
V VVGS VGS(off)
VGSQ
Vgs
예제 9 1 VGSQ예제 9-1
![Page 7: Ch. 9Ch. 9 FET Amplifiers and Sihi i iSwitching circuitselearning.kocw.net/contents4/document/lec/2013/Hanky… · · 2013-08-30Yun SeopYu 동작 JFET 증폭기 - RG: 0V d0V dc로](https://reader034.fdocument.pub/reader034/viewer/2022042502/5aee4a6b7f8b9ac57a8bc207/html5/thumbnails/7.jpg)
Yun SeopYuFET 증폭
등가회로
gm = ΔID/ΔVGS 교류 gm = gm D GS gmId/Vgs
DId = gmVgsD
G gmVgsgmVgs r’d
간략화된 모델
Vgs
G gmVgs
G
r dsr′gs r’gs and r’ds
∞
SVgs
SS
![Page 8: Ch. 9Ch. 9 FET Amplifiers and Sihi i iSwitching circuitselearning.kocw.net/contents4/document/lec/2013/Hanky… · · 2013-08-30Yun SeopYu 동작 JFET 증폭기 - RG: 0V d0V dc로](https://reader034.fdocument.pub/reader034/viewer/2022042502/5aee4a6b7f8b9ac57a8bc207/html5/thumbnails/8.jpg)
Yun SeopYuFET 증폭
전압이득
Vout= VdsD
G
IdD
RAv = |Vout/Vin|
VgsgmVgs
Rdv out/ in
= |-IdRd/Vgs|
S = |-gmVgs Rd/Vgs|
g R= gmRd
![Page 9: Ch. 9Ch. 9 FET Amplifiers and Sihi i iSwitching circuitselearning.kocw.net/contents4/document/lec/2013/Hanky… · · 2013-08-30Yun SeopYu 동작 JFET 증폭기 - RG: 0V d0V dc로](https://reader034.fdocument.pub/reader034/viewer/2022042502/5aee4a6b7f8b9ac57a8bc207/html5/thumbnails/9.jpg)
Yun SeopYuFET 증폭
예제 9-1) JFET gm = 4 mS, Rd = 1.5 kΩ Av ?
Av = gmRd = (4m)(1.5k) = 6
![Page 10: Ch. 9Ch. 9 FET Amplifiers and Sihi i iSwitching circuitselearning.kocw.net/contents4/document/lec/2013/Hanky… · · 2013-08-30Yun SeopYu 동작 JFET 증폭기 - RG: 0V d0V dc로](https://reader034.fdocument.pub/reader034/viewer/2022042502/5aee4a6b7f8b9ac57a8bc207/html5/thumbnails/10.jpg)
Yun SeopYuFET 증폭
이득에서 외부 소스저항의 영향
V Vi = V + g V RSVout
IdD
Vin = Vgs + gmVgs RS
Av = |Vout/Vin|
VgmVgs
G
R
= |-IdRd/[(1+ gmRS)Vgs]|
[( ) ]Vgs
S
Rd = |-gmVgsRd/[(1+ gmRS)Vgs]|
= g Rd/(1+ g RS)RS
= gmRd/(1+ gmRS)
Av 감소
예제-extra) gm = 4 mS, Rd = 1.5 kΩ, RS = 560Ω Av ?
A = g R /(1+ g R ) = (4m)(1 5k)/[1+(4m)(560)]=1 85 감소Av= gmRd/(1+ gmRS) = (4m)(1.5k)/[1+(4m)(560)]=1.85 감소
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Yun SeopYu공통 소스 증폭기 (CS Amp.)
JFET CS Amp.
• 분석절차1. dc 분석
바이어스 체크 (Q점)2. Ac 분석
a. Capacitor shortb. inductor openc. dc source groundd. 등가회로 삽입
증폭이득 입력저항증폭이득, 입력저항,출력 저항 등 체크
![Page 12: Ch. 9Ch. 9 FET Amplifiers and Sihi i iSwitching circuitselearning.kocw.net/contents4/document/lec/2013/Hanky… · · 2013-08-30Yun SeopYu 동작 JFET 증폭기 - RG: 0V d0V dc로](https://reader034.fdocument.pub/reader034/viewer/2022042502/5aee4a6b7f8b9ac57a8bc207/html5/thumbnails/12.jpg)
Yun SeopYu공통 소스 증폭기 (CS Amp.)
JFET CS Amp. – dc 분석 (Q점)
Va. 중점 바이어스 이용
ID = IDSS/2, VGS = VGS(off) /3.4
+VDD
R I
b. Otherwise, ID 계산:
2⎞⎛
RD
VG
VD
ID
2
)( ||1 ⎟
⎟⎠
⎞⎜⎜⎝
⎛+=
offGS
SDDSSD V
RIIIR
VG
VS)( || ⎠⎝ offGS
VGS = -VS = -IDRS.ID : 이차방정식의 해
RS
RG
Then, VDS = VD-VS = VDD-ID(RD+RS)DC Equivalentcircuitcircuit
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Yun SeopYu공통 소스 증폭기 (CS Amp.)
JFET CS Amp.– ac 분석
Rin: very high IG ≈ 0
Vgs = Vin
Av = |Vout/Vin|
Vout
IdD
Av = |Vout/Vin|
= |-IdRd/Vgs| = gmRd
Rd = RD//RL
V A V R V
RdVinV
G
d
Vout = AvVin = gmRdVin
위상 반전
IGSS 고려하면RG
VgsgmVgs
SGSS
⎟⎟⎠
⎞⎜⎜⎝
⎛= GS
Gin IVRR //
AC equivalent circuit
⎟⎠
⎜⎝ GSSI
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Yun SeopYu공통 소스 증폭기 (CS Amp.) -예제9-5
예제 9-4 수정) JFET IDSS = 8 mS, VGS(off) = -10V
VDD = 12 V, RD = 3.3 kΩ, RS = 2.7 kΩ, RG = 10 MΩ, Vin = 100 mVrms
- dc 분석 (Q점)
+VDD VG = 0 VGS = VG-VS = - VS
I RRD
VVD
ID =-IDRS2
1 ⎟⎟⎞
⎜⎜⎛−= GS
DSSDVII
R
VG
VS
2
)(
1 ⎟⎞
⎜⎛+
⎟⎠
⎜⎝
SD
offGSDSSD
RII
V
RS
RG
)(
1 ⎟⎟⎠
⎜⎜⎝+=
offGS
SDDSS V
I
이차 방정식 해: ID이차 방정식 해: ID
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Yun SeopYu공통 소스 증폭기 (CS Amp.) -예제9-5
],2[1 22)(
2)(2
)(
2
)(
++=⎟⎟⎠
⎞⎜⎜⎝
⎛+= RIRIVV
VI
VRIII SDSDoffGSoffGS
offGS
DSS
offGS
SDDSSD
0012 2
)(
22
)(
2
)()(
=++>−−=+⎟⎟⎠
⎞⎜⎜⎝
⎛−+
⎠⎝
CBIAIIIV
IRIV
IRDDDSSD
offGS
DSSSD
offGS
DSSS
ffff
)()( ⎠⎝ ffff
2 2DSS S
2 2GS(off)
I R (8m)(2.7k)A 583.2,V ( 10)
= = =−
S DSS
GS(off)
2R I (2)(2.7k)(8m)B 1 1 5.32,V 10
C I 8m
=− + =− + =−−
= =DSS
22
D
C I 8m,
( 5.32) ( 5.32) 4(583.2)(8m)4I 7.2mA, 1.9mA2 2(583.2)
B B ACA
= =
− − ± − −− ± −= = =
D DD D D
S
( )V V I R 12 (1.9m)(3.3k) 5.73VV= − = − =
D SI R (1.9m)(2.7k) 5.13VV V V V 513V= = =
GS G S SV V V V 5.13V= − =− =−
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Yun SeopYu공통 소스 증폭기 (CS Amp.) -예제9-5
– ac 분석 Vout
IdD
RDVing V
G
RG
VgsgmVgs
S
Av = |Vout/Vin| =|-IdRD/Vgs|
5.13
,1.6mS10
2(8m)||
2
)(
−
===
GS
offGS
DSSmO
V
VIg
Av |Vout/Vin| | IdRD/Vgs|
=|-gmVgsRD/Vgs| = gmRD
=(779μ)(3.3k) = 2.57S779)
105.13(1.6m)(1)1(
)(
μ=−
−=−=offGS
GSmOm V
Vgg( μ)( )
Vout = AvVin = (2.57)(100mVrms)= 257 mV= 257 mVrms
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Yun SeopYu공통 소스 증폭기 (CS Amp.) -예제9-6
예제 9-5 extra와 같으나 부하에 부하저항 RL =4.7 kΩ 이 있는 경우Av ?
Vout
IdD
RdVinV
G
d
RG
VgsgmVgs
S
R = R //R =(3 3k)||(4 7k)=1 94 kΩRd = RD//RL=(3.3k)||(4.7k)=1.94 kΩ
Av = |Vout/Vin| =|-IdRd/Vgs|=|-gmVgsRd/Vgs| = gmRd =(779μ)(1.94k) = 1.5감소감소
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Yun SeopYu공통 소스 증폭기 (CS Amp.) -예제9-7
예제 9-6) JFET VGS = 10 V IGSS = 30 nA 입력저항 Rin ?
VDD = 18 V, RD = 1 kΩ, RS = 100 Ω, RG = 10 MΩ, RL = 10 kΩ
// ⎟⎟⎠
⎞⎜⎜⎝
⎛= GS
Gin IVRR
IGSS
9.7MΩ31010M)//( =⎟⎠⎞
⎜⎝⎛=
⎟⎠
⎜⎝ GSSI
3n)( ⎟
⎠⎜⎝
Rin RIN(gate)=VGS/IGSS
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Yun SeopYu공통 소스 증폭기 (CS Amp.)
D-MOSFET CS Amp.
dc/ac 분석은 JFET과 유사
ID = IDSS at VGS = 0
Once ID is known,
V V I RVD= VDD - IDRD
Av = gmRd
![Page 20: Ch. 9Ch. 9 FET Amplifiers and Sihi i iSwitching circuitselearning.kocw.net/contents4/document/lec/2013/Hanky… · · 2013-08-30Yun SeopYu 동작 JFET 증폭기 - RG: 0V d0V dc로](https://reader034.fdocument.pub/reader034/viewer/2022042502/5aee4a6b7f8b9ac57a8bc207/html5/thumbnails/20.jpg)
Yun SeopYu공통 소스 증폭기 (CS Amp.)- 예제 extra
예제 extra) D-MOSFET, IDSS = 12 mA, gm = 3.2 mSVDD = 15 V, RD = 620 Ω, RG = 10 MΩ, RL = 8.2 kΩ, Vin = 500 mVmVrms
DC 분석
ID
IG= 0 VG = 0 VGS
= 0
ID = IDSS = 12 mA
VD
ID ID = IDSS = 12 mA
VG
VDS = VD= VDD – IDRDVDS VD VDD IDRD
= 15 – (12m)(620) = 7.56 V
![Page 21: Ch. 9Ch. 9 FET Amplifiers and Sihi i iSwitching circuitselearning.kocw.net/contents4/document/lec/2013/Hanky… · · 2013-08-30Yun SeopYu 동작 JFET 증폭기 - RG: 0V d0V dc로](https://reader034.fdocument.pub/reader034/viewer/2022042502/5aee4a6b7f8b9ac57a8bc207/html5/thumbnails/21.jpg)
Yun SeopYu공통 소스 증폭기 (CS Amp.)- 예제 9-8
AC 분석
Vout
ID
Rd = RD//RL=(620)||(8.2k)=576 Ω
RdVG
Id Av = |Vout/Vin| =|-IdRd/Vgs|
=|-gmVgsRd/Vgs| = gmRd
(3 2 )(576) 1 843d
RG
Vin
VgsgmVgs
S
=(3.2m)(576) = 1.843
V A V (1 843)(500 V )S Vout = AvVin = (1.843)(500mVrms)= 922 mVrms
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Yun SeopYu공통 소스 증폭기 (CS Amp.)
E-MOSFET CS Amp.
![Page 23: Ch. 9Ch. 9 FET Amplifiers and Sihi i iSwitching circuitselearning.kocw.net/contents4/document/lec/2013/Hanky… · · 2013-08-30Yun SeopYu 동작 JFET 증폭기 - RG: 0V d0V dc로](https://reader034.fdocument.pub/reader034/viewer/2022042502/5aee4a6b7f8b9ac57a8bc207/html5/thumbnails/23.jpg)
Yun SeopYu공통 소스 증폭기 (CS Amp.)
E-MOSFET CS Amp. – dc 분석 (Q점)
IDDDG V
RRRV ⎟⎟
⎠
⎞⎜⎜⎝
⎛+
= 2
VD
ID RR ⎟⎠
⎜⎝ + 21
VS = 0VGS = VG - VS = VG
VG
IG≈0
( )2)(thGSGSD VVKI −=VG
VSVDS = VDD – IDRD
![Page 24: Ch. 9Ch. 9 FET Amplifiers and Sihi i iSwitching circuitselearning.kocw.net/contents4/document/lec/2013/Hanky… · · 2013-08-30Yun SeopYu 동작 JFET 증폭기 - RG: 0V d0V dc로](https://reader034.fdocument.pub/reader034/viewer/2022042502/5aee4a6b7f8b9ac57a8bc207/html5/thumbnails/24.jpg)
Yun SeopYu공통 소스 증폭기 (CS Amp.)
E-MOSFET CS Amp. – ac 분석
Rin: very high IG ≈ 0
Vgs = Vin
Av = Vout/VinVAv = Vout/Vin
= -IdRd/Vgs = -gmRd
Rd = RD//RL
V A V R V
Vout
Id
Vout = AvVin = -gmRdVin
IGSS 고려하면RdVin
VgmVgs
G
gateINin RRRR = )(21 ////R1//R2
Vgsgm gs
R
GSgateIN
gateINin
IVR =)(
)(21
AC i l i i
RinRIN(gate)
GSSIAC equivalent circuit
![Page 25: Ch. 9Ch. 9 FET Amplifiers and Sihi i iSwitching circuitselearning.kocw.net/contents4/document/lec/2013/Hanky… · · 2013-08-30Yun SeopYu 동작 JFET 증폭기 - RG: 0V d0V dc로](https://reader034.fdocument.pub/reader034/viewer/2022042502/5aee4a6b7f8b9ac57a8bc207/html5/thumbnails/25.jpg)
Yun SeopYu공통 소스 증폭기 (CS Amp.)-예제 9-8 extra
E-MOSFET CS Amp. VGS(th) = 4 V, VGS = 10 V ID(on) = 5 mA, VDD = 15 V, gm = 5.5 mS, RD = 3.3 kΩ, R1 = 47 kΩ, R2 = 33 kΩ, RL = 33 kΩ, Vin = 50 mVrms
– dc 분석 (Q점)2 ⎟⎞
⎜⎛
VRV
ID 19V6(15)47k21
2
=⎟⎞
⎜⎛=
⎟⎟⎠
⎞⎜⎜⎝
⎛+
= DDG VRR
RV
VD
ID
IG≈0
19V.6(15)k3347k
=⎟⎠
⎜⎝ +
=
VGS = VG = 6.19 V
( )2
5I
VG
VS
( )
0667 A1).19(0.319m)(6 2
2)(
−=
−= thGSGSD VVKI
( ) ( )2
22)(
)(
mA/V1390
4105m−
=−
=thGSGS
onD
VVI
K0.667mA=
VDS = VD = VDD – IDRD
=15-(0.667m)(3.3k)12 8VmA/V139.0= =12.8V
![Page 26: Ch. 9Ch. 9 FET Amplifiers and Sihi i iSwitching circuitselearning.kocw.net/contents4/document/lec/2013/Hanky… · · 2013-08-30Yun SeopYu 동작 JFET 증폭기 - RG: 0V d0V dc로](https://reader034.fdocument.pub/reader034/viewer/2022042502/5aee4a6b7f8b9ac57a8bc207/html5/thumbnails/26.jpg)
Yun SeopYu공통 소스 증폭기 (CS Amp.)-예제9-9 extra
AC 분석
Rd = RD//RL=(3.3k)||(33k)=3 kΩ
Vout
I
Av = |Vout/Vin| =|-IdRd/Vgs|
=|-gmVgsRd/Vgs| = gmRd
(5 5 )(3k) 16 5
RdVG
Id =(5.5m)(3k) = 16.5
V A V (16 5)(50 V )Rd
R1//R2
Vin
VgsgmVgs
Vout = AvVin = (16.5)(50mVrms)= 825 mVrms
![Page 27: Ch. 9Ch. 9 FET Amplifiers and Sihi i iSwitching circuitselearning.kocw.net/contents4/document/lec/2013/Hanky… · · 2013-08-30Yun SeopYu 동작 JFET 증폭기 - RG: 0V d0V dc로](https://reader034.fdocument.pub/reader034/viewer/2022042502/5aee4a6b7f8b9ac57a8bc207/html5/thumbnails/27.jpg)
Yun SeopYu공통 드레인 증폭기 (CD Amp.)
Source Follower – dc 분석 (Q점)
VGS = VG – VS
= 0 - IDRSD S
= -IDRS
![Page 28: Ch. 9Ch. 9 FET Amplifiers and Sihi i iSwitching circuitselearning.kocw.net/contents4/document/lec/2013/Hanky… · · 2013-08-30Yun SeopYu 동작 JFET 증폭기 - RG: 0V d0V dc로](https://reader034.fdocument.pub/reader034/viewer/2022042502/5aee4a6b7f8b9ac57a8bc207/html5/thumbnails/28.jpg)
Yun SeopYu공통 드레인 증폭기 (CD Amp.)
Source Follower – ac 분석
Rin = RG//RIN(gate)
Vout = IdRs = gmVgsRsIdD
g
Rs= RS//RL
Vin = Vgs + IdRs = Vgs+ g V R = V (1+g R )
Vin gmVgs
G
d
gmVgsRs = Vgs(1+gmRs)
1== smout
vRgVARs = RS//RL
RG
Vgs VoutS
11
≈+ smin
v RgVRIN(gate)Rin
gmRs >> 1
AC equivalent circuit
gm s
![Page 29: Ch. 9Ch. 9 FET Amplifiers and Sihi i iSwitching circuitselearning.kocw.net/contents4/document/lec/2013/Hanky… · · 2013-08-30Yun SeopYu 동작 JFET 증폭기 - RG: 0V d0V dc로](https://reader034.fdocument.pub/reader034/viewer/2022042502/5aee4a6b7f8b9ac57a8bc207/html5/thumbnails/29.jpg)
Yun SeopYu공통 드레인 증폭기 (CD Amp.)-예제9-10
그림 9-21 규격표 (최소값 선택) 이용 Av, Rin ?
P 채널 JFET, IDSS = 1 mA, VGS(off) = 0.75 V, gm = 1000μS, VGS = 20 V I 5nA20 V IGSS = 5nA,
RS = 10 kΩ, RG = 10 MΩ, RL = 10 MΩ, VDD = 10 V, Vin = 50 mVrms
ID
2N5460 V g VG
Id
2N5460
R R //RRG
Vin
Vgs
gmVgs
VoutS
Rs = RS//RL
RIN(gate)Rin
R R //R (10k)||(10M) 10 kΩ
0.909(1m)(10k)1
(1m)(10k)1
|| =+
=+
=+
=+
==sm
sm
gsmsgs
gsms
dsgs
ds
in
outv Rg
RgVgRV
VgRIRV
IRVVA
Rs= RS//RL = (10k)||(10M) ≈ 10 kΩ
smgsmsgsdsgsin
Ω≈==
===
MMMRRRnI
VR
gateINGin
GSS
GSgateIN
10)400//()10(//
MΩ400520
)(
)(
![Page 30: Ch. 9Ch. 9 FET Amplifiers and Sihi i iSwitching circuitselearning.kocw.net/contents4/document/lec/2013/Hanky… · · 2013-08-30Yun SeopYu 동작 JFET 증폭기 - RG: 0V d0V dc로](https://reader034.fdocument.pub/reader034/viewer/2022042502/5aee4a6b7f8b9ac57a8bc207/html5/thumbnails/30.jpg)
Yun SeopYu공통 게이트 증폭기 (CG Amp.)
– dc 분석 (Q점)자기 바이어스
![Page 31: Ch. 9Ch. 9 FET Amplifiers and Sihi i iSwitching circuitselearning.kocw.net/contents4/document/lec/2013/Hanky… · · 2013-08-30Yun SeopYu 동작 JFET 증폭기 - RG: 0V d0V dc로](https://reader034.fdocument.pub/reader034/viewer/2022042502/5aee4a6b7f8b9ac57a8bc207/html5/thumbnails/31.jpg)
Yun SeopYu공통 게이트 증폭기 (CG Amp.)
– ac 분석
gs
dd
in
outv V
RIVVA
−−
==Vout
IdD
dmdgsm
gsin
RgRVg==gmVgs
G
d
Rd
Vgsdm
gs
gV
1gsi VV −RS
Vin
SRd
Rin(source)
)(1
mgsm
gs
in
insourcein gVg
VIVR =
−==Rin
)(// sourceinSin RRR =AC equivalent circuit
![Page 32: Ch. 9Ch. 9 FET Amplifiers and Sihi i iSwitching circuitselearning.kocw.net/contents4/document/lec/2013/Hanky… · · 2013-08-30Yun SeopYu 동작 JFET 증폭기 - RG: 0V d0V dc로](https://reader034.fdocument.pub/reader034/viewer/2022042502/5aee4a6b7f8b9ac57a8bc207/html5/thumbnails/32.jpg)
Yun SeopYu공통 게이트 증폭기 (CG Amp.) – 예제 9-11
그림 9-21 규격표 (최소값 선택) 이용 Av, Rin ?
P 채널 JFET (2N5462) CG Amp., gm = 2000 μS,
R 4 7 kΩ R 10 kΩ R 10 kΩ V 15 VRS = 4.7 kΩ, RD = 10 kΩ, RL = 10 kΩ, VDD = 15 V
Vout
ID
VG
Id
VgsRd= RD//RL
( ) ( )
2N5462R
Vin
gmVgs
S
Vgs
Rin(source)
= (10k)||(10k) = 5 kΩ
RVRIV
RSin
Rin
10)5)(2000( ====−−
== kRgV
RVgVRI
VVA dm
gs
dgsm
gs
dd
in
outv μ
Ω−
50011gsin VVR
Ω===
Ω===−
==
45200)(4.7k)//(5//
5002000
)(
)(
sourceinSin
mgsm
g
in
insourcein
RRR
gVgIR
μ
![Page 33: Ch. 9Ch. 9 FET Amplifiers and Sihi i iSwitching circuitselearning.kocw.net/contents4/document/lec/2013/Hanky… · · 2013-08-30Yun SeopYu 동작 JFET 증폭기 - RG: 0V d0V dc로](https://reader034.fdocument.pub/reader034/viewer/2022042502/5aee4a6b7f8b9ac57a8bc207/html5/thumbnails/33.jpg)
Yun SeopYu
![Page 34: Ch. 9Ch. 9 FET Amplifiers and Sihi i iSwitching circuitselearning.kocw.net/contents4/document/lec/2013/Hanky… · · 2013-08-30Yun SeopYu 동작 JFET 증폭기 - RG: 0V d0V dc로](https://reader034.fdocument.pub/reader034/viewer/2022042502/5aee4a6b7f8b9ac57a8bc207/html5/thumbnails/34.jpg)
Yun SeopYu
Homework
All Examples
Selected Problems(P.497-503): 10 11 20 24 30503): 10, 11, 20, 24, 30
34
![Page 35: Ch. 9Ch. 9 FET Amplifiers and Sihi i iSwitching circuitselearning.kocw.net/contents4/document/lec/2013/Hanky… · · 2013-08-30Yun SeopYu 동작 JFET 증폭기 - RG: 0V d0V dc로](https://reader034.fdocument.pub/reader034/viewer/2022042502/5aee4a6b7f8b9ac57a8bc207/html5/thumbnails/35.jpg)
Yun SeopYu
![Page 36: Ch. 9Ch. 9 FET Amplifiers and Sihi i iSwitching circuitselearning.kocw.net/contents4/document/lec/2013/Hanky… · · 2013-08-30Yun SeopYu 동작 JFET 증폭기 - RG: 0V d0V dc로](https://reader034.fdocument.pub/reader034/viewer/2022042502/5aee4a6b7f8b9ac57a8bc207/html5/thumbnails/36.jpg)
Yun SeopYu
![Page 37: Ch. 9Ch. 9 FET Amplifiers and Sihi i iSwitching circuitselearning.kocw.net/contents4/document/lec/2013/Hanky… · · 2013-08-30Yun SeopYu 동작 JFET 증폭기 - RG: 0V d0V dc로](https://reader034.fdocument.pub/reader034/viewer/2022042502/5aee4a6b7f8b9ac57a8bc207/html5/thumbnails/37.jpg)
Yun SeopYuActive Antenna
- An active antenna driving a receiver or a coax through a buffer
The low output impedance buffer can be a BJT emitter-follower or p pan impedance-matching transformer.
![Page 38: Ch. 9Ch. 9 FET Amplifiers and Sihi i iSwitching circuitselearning.kocw.net/contents4/document/lec/2013/Hanky… · · 2013-08-30Yun SeopYu 동작 JFET 증폭기 - RG: 0V d0V dc로](https://reader034.fdocument.pub/reader034/viewer/2022042502/5aee4a6b7f8b9ac57a8bc207/html5/thumbnails/38.jpg)
Yun SeopYuActive Antenna
- Cascode amplifier for active antenna
This active antenna has a voltagegain of approximately 2000 at 88MH d i f i t lMHz and a gain of approximately10,000 at 1 GHz which makes itapplicable for the FM broadcastband some TV channel bandsband, some TV channel bands,some amateur radio (HAM) bands,cell phone bands, and manyothersothers.
![Page 39: Ch. 9Ch. 9 FET Amplifiers and Sihi i iSwitching circuitselearning.kocw.net/contents4/document/lec/2013/Hanky… · · 2013-08-30Yun SeopYu 동작 JFET 증폭기 - RG: 0V d0V dc로](https://reader034.fdocument.pub/reader034/viewer/2022042502/5aee4a6b7f8b9ac57a8bc207/html5/thumbnails/39.jpg)
Yun SeopYuActive Antenna
Simulate the active antenna circuit using your Multisim software.Measure the output voltage at 10 MHz, 100 MHz, and 500 MHz.