전자회로I
다섯째주 1강
Chapter 3
Lecture Homepage : http://signal.korea.ac.kr
2016년 6월 27일2 pages
Operation of the npn Transistor in the Active mode The collector Current
we can express the collector current iC as
(5.3) / TBE VvSC eIi
The saturation current Is is given by
WnqDAI pnES /0
Substituting nP0 = ni2/NA, where ni is the intrinsic carrier density and NA
is the doping concentration in the base, we can express IS as
(5.4) 2
WNnqDAI
A
inES
Chapter 3
Lecture Homepage : http://signal.korea.ac.kr
2016년 6월 27일3 pages
Operation of the npn Transistor in the Active mode The Base Current
(5.5) /2
1TBE Vv
pD
ipEB e
LNnqDA
i
The base current iB is composed of two components
(5.6) 2b
nB
Qi
Chapter 3
Lecture Homepage : http://signal.korea.ac.kr
2016년 6월 27일4 pages
Operation of the npn Transistor in the Active mode The Base Current
WnqAQ pEn )0(21
Substituting for np(0) from Eq. (5.1) and replacing np0 by ni2/NA gives
(5.7) 2
/2
TBE Vv
A
iEn e
NqWnAQ
which can be substituted in Eq. (5.6) to obtain
(5.8) 21 /
2
2TBE Vv
Ab
iEB e
NqWnAi
Combining Eqs. (5.5) and (5.8) and utilizing Eq. (5.4), we obtain for thetotal base current iB the expression
(5.9) e W21 TBE/Vv
2
bnpD
A
n
pSB DL
WNN
DD
Ii
Chapter 3
Lecture Homepage : http://signal.korea.ac.kr
2016년 6월 27일5 pages
Operation of the npn Transistor in the Active mode The Base Current
Comparing Eqs. (5.3) and (5.9), we see that iB can be expressed as afraction of iC as follows :
(5.10) C
Bii
(5.11) TBE /VvSB eIi
(5.12) 21/1
2
bpD
A
n
p WLW
NN
DD
Chapter 3
Lecture Homepage : http://signal.korea.ac.kr
2016년 6월 27일6 pages
Operation of the npn Transistor in the Active mode The Emitter Current
(5.19) 1
(5.18) )/(
(5.17) 1
(5.16)
)15.5(1
(5.14) 1(5.13)
/
/
TBE
TBE
VvSE
EC
VvSE
CE
BCE
eIi
ii
eIi
ii
iii
Chapter 3
Lecture Homepage : http://signal.korea.ac.kr
2016년 6월 27일7 pages
Equivalent-Circuit Models
Chapter 3
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2016년 6월 27일8 pages
Structure of Actual Transistors
Chapter 3
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2016년 6월 27일9 pages
Minority Carrier Concentration in Saturation Mode
Chapter 3
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2016년 6월 27일10 pages
The pnp Transistor
Chapter 3
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2016년 6월 27일11 pages
Equivalent Circuit Model: PNP Transistor
Chapter 3
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2016년 6월 27일12 pages
Circuit Symbols and Conventions
Chapter 3
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2016년 6월 27일13 pages
Current-Voltage CharacteristicsGraphical Representation of Transistor Characteristics
/ VBE TC Si I e
Chapter 3
Lecture Homepage : http://signal.korea.ac.kr
2016년 6월 27일14 pages
Current-Voltage CharacteristicsGraphical Representation of Transistor Characteristics