SOLUTIONS MANUAL
, Contents
Page
Chapter 1 Basic Diode Circuits 1
Chapter 2 Basic Principles of Semiconductors 39
Chapter 3 pn Junction and Semiconductor Diodes 51
Chapter 4 Semiconductor Fabrication 65
Chapter 5 Field Effect Transistors 67
Chapter 6 Bipolar Junction Transistor 93
Chapter 7 Two-Port Circuits, Amplifiers, and Feedback 109
Chapter 8 Single-Stage Transistor Amplifiers 129
Chapter 9 Multistage and Feedback Amplifiers 185
Chapter 10 Differential and Operational Amplifiers 215
Chapter 11 Power Amplifiers and Switches 245
Chapter 12 Basic Elements of Digital Circuits 273
Chapter 13 Digital Logic Circuit Families 293
Companion CD: Classroom Presentations
Figures
, Chapter 1 Basic Diode Circuits
Solutions to Exercises
E1.1.1 ( )
(a) -0.99IS = IS eVD / 2VT − 1 ; vD = 0.052ln0.01 = -0.24 V.
( )
(b) 100IS = IS eVD / 2VT − 1 ; vD = 0.052ln101 = 0.24 V.
0.052
E1.1.2 (a) rd = = 5.2 Ω.
10 − 10 − 8
−2
iD 10 −2
(b) vD = 0.052 ln = 0.052 ln − 8 = 0.718 V.
IS 10
(c) vD = 0.052ln(2×106) = 0.754 V.
E1.2.1 (a) Vγ ≅ 0.18 V, 10
VDO ≅ 0.42 V.
8
(b) Vγ ≅ 0.5 V,
IS = 1 μA IS = 1 nA
VDO ≅ 0.78 V.
6
For both diodes: iD
mA
rD ≅ 0.052 V/10 mA 4
= 5.2 Ω.
2
0
0 0.2 0.4 0.6 0.8
( )
vD V
E1.2.3 i D = IS e v D /ηVT − 1 .
−6
/(10 −6 ×0.026 )
The exponential becomes e10 = e1/ 0.026 and
10 −12 e1/ 0.026 = 5.1× 10 4 A.
dv L dv L
E1.3.1 From Equation 1.3.4, = -ωVmsinθ1 . From Equation 1.3.7,
dt ωt =θ1 dt ωt =θ1
1 1
= -ωVmcosθ1 × . Equating these slopes gives tanθ1 = . Note that
ωCRL ωCRL
vL is continuous because there are no current impulses to change the
capacitor voltage at ωt = θ1. Moreover, because vL appears across a resistor,
the capacitor current must also be continuous at this instant.
1
, 180 1
E1.3.2 (a) ωCRL = 100π × 5 × 10 −6 × 10 4 = 5π = 15.71, θ1 = tan −1 = 3.64°. θ2
π 5π
is determined by solving Equation 1.3.8: cosθ2 = cosθ1 e ( −π +θ1 +θ2 ) / 5π .
Performing a numerical analysis starting with θ2 = π /6 gives θ2 = 31.8°;
θ1 + θ 2
Vmin = 50[− cos(π − θ 2 )] = 50cosθ2 = 42.5 V; × 100 = 19.7%
180 o
180 1
(b) θ1 = tan −1 = 1.15°. θ2 is determined by solving Equation 1.3.8:
π 50
cosθ2 = cosθ1 e ( −π +θ1 +θ2 ) / 5π . Performing a numerical analysis starting with
θ1 + θ 2
θ2 = π /9 gives θ2 = 19.0°; Vmin = 50cosθ2 = 47.3 V; × 100 = 11.2% .
180 o
⎛T ⎞ I T
E1.3.3 Total charge qD = IDCTcd + I DC ⎜ − Tcd ⎟ . Dividing by Tcd gives iD(av)cd = DC .
⎝2 ⎠ 2 Tcd
Vm′ i Dpk
Substituting for Tcd from Equation 1.3.14: iD(av)cd = I DC π ≅ , using
2v r 2
Equation 1.2.15.
E1.3.4 As the capacitor discharges, the decaying exponential intersects the next
positive half cycle at 2π – θ2 instead of π – θ2. Hence, Equation 1.3.8 is
modified to cosθ2 = cosθ1 e −[2π − (θ1 +θ2 )] / ωCRL ≅ e − 2π / ωCRL = 1 −
1
.
fCRL
Vm′
Assuming that during discharge, IDC is constant and equals , the
vr
discharge period is nearly T or 1/f. The charge in capacitor voltage is
I DC I
therefore = v r . Equation 1.3.11 becomes VDC = Vm′ – D . In other
fC 2fC
words, the peak-to-peak ripple is doubled. Using the approximation, cosα ≈
α2 1 θ2 1
1− ,1− = 1 − 2 , so θ2 = . Because the ripple is doubled,
2 fCR L 2 fCR L
θ 22
Vm′ (1 – cosθ2) is doubled. Using the approximation 1 – cosθ2 = , this
2
θ2 1 2
means that θ2 is multiplied by 2 . The conduction angle is = .
ω 2πf fCR L
2