전자 회로 1
Lecture 5 (Diode II)
2009. 04.
임한조
아주대학교 전자공학부
hanjolim@ajou.ac.kr
이 강의 노트는 전자공학부 곽노준 교수께서 08.03에 작성한 것으로 노트제공에 감사드림.
Review
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Open circuit:
ID = IS
Reverse-bias:
I = IS - ID ~= IS
Breakdown
(large reverse-bias):
almost constant V
Forward-bias:
I = ID – IS ~=ID
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Current exponentially
increases
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Forward-bias
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Why n?  n=1 or 2. fabrication dependent
Normally i >> Is 
Temperature
dependence
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Load line
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I D  I S e VD / nVT
(3.6)
VDD  VD
ID 
R
(3.7)
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Various diode modeling
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Exponential model
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calculator solution
Iterative analysis (see Example 3.4)
Piecewise linear model
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Example 3.5
VDD = 5V, R = 1kohm
model: VD0 = 0.65V, rD = 20 ohm
VDD  VD 0
ID 
R  rD
5  0.65
ID 
 4.26 mA
1  0.02
VD  VD 0  I D rD
 0.65  4.26  0.02  0.735 V
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Constant voltage drop model
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The Small-Signal Model
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V-I @ bias:
Small perturbation:
(
)
Taylor series approximation
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Small signal resistance (incremental resistance)
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Zener Diode
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Mostly used for voltage regulator
knee current
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Example 3.8
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Applications: Rectifier Circuits
Zener diode
See Chap. 3.4
Diode circuit
See Chap. 3.5
RC circuit
with large time constant
(low pass filter)
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The half-wave rectifier
PIV = Vs : Peak inverse voltage PIV < VZ
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The full-wave rectifier
PIV = 2Vs  VD
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The bridge rectifier
 D 3 (revers) = O +  D 2 (forward)
PIV = Vs  2VD  VD  Vs  VD
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The peak rectifier (with LPF: RC
circuit)
Ideal: no load
With load
i L  O / R
i D  iC  i L
 C
d I
 iL
dt
(3.23)
(3.24)
(3.25)
If vI < vO :
Time constant
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Limiter Circuits
Soft limiting
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Clamping Circuits
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Voltage Doubler
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신호 검출기로서의 pn 다이오드
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빛을 전기로, 전기를 빛으로
- 빛의 흡수
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- 자연방출
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- 유도방출
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pn 접합 발광 다이오드
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pn 접합 발광 다이오드의 응용
Left: La Cittadella, a retail and cinema complex in Kawasaki, Japan, contains a 130 foot high tower illuminated by a variety of intelligent
LED lighting effects including rainbow patterns and gradual color shifts. The complex's architect is the Jerde Partnership International,
Inc, and the LED illumination is by Color Kinetics. (Photo: Masami Soto.) Center: three bridges across the Clyde river in Glasgow have
been illuminated with high-intensity LED lighting. Luxeon LEDs from Lumileds and Philips floodlights were used in the installations.
(Photo: Philips). Right: the Gazi Technopolis in Athens, Greece, designed by Duilio Passariello of Philips LiDAC Europe. (Photo: Philips.)
http://www.compoundsemiconductor.net/
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pn 접합 발광 다이오드의 응용
현대자동차 HCD-8 Concept Tourer
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Kawasaki's La Cittadella complex
also includes a fountain illuminated
by constantly changing colored LED
lights. (Photo: Masami Soto.)
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pn 접합 수광 다이오드
I [mA]
1.0
빛의 세기 = 0
0.5
빛의 세기 = I
빛의 세기 = 2I
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0.0
-5
-4
-3
-2
-1
V [V]
0
1
-0.5
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pn 접합 태양전지
+ V −
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