chapter 1 - introduction to electronics introduction microelectronics integrated circuits (ic)...
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Chapter 1 - Introduction to Electronics
Introduction
Microelectronics
Integrated Circuits (IC) Technology
Silicon Chip
Microcomputer / Microprocessor
Discrete Circuits
Signals
Signal ProcessingTransducers
http://www.eas.asu.edu/~midle/jdsp/jdsp.html
Signals
Voltage Sources
Current Sources
Thevenin & Norton
http://www.clarkson.edu/%7Esvoboda/eta/ClickDevice/refdir.htmlhttp://www.clarkson.edu/%7Esvoboda/eta/Circuit_Design_Lab/circuit_design_lab.htmlhttp://www.clarkson.edu/%7Esvoboda/eta/CircuitElements/vcvs.html
Figure 1.1 Two alternative representations of a signal source: (a) the Thévenin form, and (b) the Norton form.
Figure 1.2 An arbitrary voltage signal vs(t).
Figure 1.3 Sine-wave voltage signal of amplitude Va and frequency f = 1/T Hz. The angular frequency v = 2pf rad/s.
Signals
Voltage Sources
Current Sources
http://www.clarkson.edu/~svoboda/eta/ClickDevice/super.htmlhttp://javalab.uoregon.edu/dcaley/circuit/Circuit_plugin.html
Signals
Voltage Sources
Current Sources
Frequency Spectrum of Signals
Fourier Series
Fourier Transform
Fundamental and Harmonics
http://www.educatorscorner.com/experiments/spectral/SpecAn3.shtml
x
frequency
time
Figure 1.4 A symmetrical square-wave signal of amplitude V.
Figure 1.5 The frequency spectrum (also known as the line spectrum) of the periodic square wave of Fig. 1.4.
Figure 1.6 The frequency spectrum of an arbitrary waveform such as that in Fig. 1.2.
Figure 1.7 Sampling the continuous-time analog signal in (a) results in the discrete-time signal in (b).
Defining the Signal or Function to be Analyzed:
f t( ) sin 0 t t( ) .2 cos 7 0 t
0 1 2 3 4 5 62
0
2
f t( )
t
Frequency Spectrum of Signals
Fourier Series
http://www.jhu.edu/%7Esignals/fourier2/index.html
Frequency Spectrum of Signals
Fourier Series
Fourier Series (Trigonometric form) of f(t):
a01
T 0
T
tf t( )
d a0 0 average value
an
2
T0
T
tf t( ) cos n 0 t
d cosine coefficients
n varying from 1 to N
10 20 30 40 50 600
0.1
an
0
n
Frequency Spectrum of Signals
Fourier Series
bn
2
T0
T
tf t( ) sin n 0 t
d sine coefficients
10 20 30 40 50 600
0.5
1
bn
0
n
Frequency Spectrum of Signals
Fourier Series
Rearranging total expression to include a0 in the complete spectrum
a1n
an
b1n
bn
c1n
1
2a1
n 2 b1n 2 c
0a0
0 10 20 30 40 50 600
0.2
0.4
c1n
0
n
Frequency Spectrum of Signals
Fourier Series
Reconstruction of time-domain function from trig. Fourier series:
f2 t( )
n1
an1
cos n1 0 t bn1
sin n1 0 t a0
0 1 2 3 4 5 62
0
2
f2 t( )
f t( )
t
Frequency Spectrum of Signals
Fourier SeriesFourier Series (Complex Form) of f(t):
wn
1
2N
n
Cn
1
T 0
tf t( ) ei wn 0 t
d
0 10 20 30 40 50 600
0.02
0.04
Cn
0
n
Fourier Transform of f(t) gives:
1
2N
12
N .25
1
2N
F 0
tf t( ) ei t
d
30 20 10 0 10 20 300
0.1
0.2
0.3
F ( )
0
The magnitude of F( ) yields the continuous frequency spectrum, and it is obviously of the form of the sampling function. The value of F(0) is A . A plot of |F( )| as a function of does not indicate the magnitude of the voltage present at any given frequency. What is it, then? Examination of F shows that, if f(t) is a voltage waveform, then F is dimensionally "volts per unit frequency," a concept that may be strange to most of us.
Frequency Spectrum of Signals
http://www.jhu.edu/%7Esignals/fourier2/index.html
Frequency Spectrum of Signals
http://www.jhu.edu/%7Esignals/listen/music1.html
http://www.jhu.edu/%7Esignals/phasorlecture2/indexphasorlect2.htm
Figure 1.8 Variation of a particular binary digital signal with time.
Figure 1.9 Block-diagram representation of the analog-to-digital converter (ADC).
Analog and Digital Signals
Sampling Rate http://www.jhu.edu/%7Esignals/sampling/index.html
Binary number systemhttp://scholar.hw.ac.uk/site/computing/activity11.asp
Analog-to-Digital Converterhttp://www.astro-med.com/knowledge/adc.htmlhttp://www.maxim-ic.com/design_guides/English/AD_CONVERTERS_21.pdf
Digital-to-Analog Converter
http://www.maxim-ic.com/ADCDACRef.cfm
Figure 1.10 (a) Circuit symbol for amplifier. (b) An amplifier with a common terminal (ground) between the input and output ports.
Figure 1.11 (a) A voltage amplifier fed with a signal vI(t) and connected to a load resistance RL. (b) Transfer characteristic of a linear voltage amplifier with voltage gain Av.
Figure 1.12 An amplifier that requires two dc supplies (shown as batteries) for operation.
Figure 1.13 An amplifier transfer characteristic that is linear except for output saturation.
Figure 1.14 (a) An amplifier transfer characteristic that shows considerable nonlinearity. (b) To obtain linear operation the amplifier is biased as shown, and the signal amplitude is kept small. Observe that this amplifier is operated from a single power supply, VDD.
Figure 1.15 A sketch of the transfer characteristic of the amplifier of Example 1.2. Note that this amplifier is inverting (i.e., with a gain that is negative).
Figure 1.16 Symbol convention employed throughout the book.
Figure 1.17 (a) Circuit model for the voltage amplifier. (b) The voltage amplifier with input signal source and load.
Figure 1.18 Three-stage amplifier for Example 1.3.
Figure 1.19 (a) Small-signal circuit model for a bipolar junction transistor (BJT). (b) The BJT connected as an amplifier with the emitter as a common terminal between input and output (called a common-emitter amplifier). (c) An alternative small-signal circuit model for the BJT.
Figure E1.20
Figure 1.20 Measuring the frequency response of a linear amplifier. At the test frequency v, the amplifier gain is characterized by its magnitude (Vo/Vi) and phase f.
Figure 1.21 Typical magnitude response of an amplifier. |T(v)| is the magnitude of the amplifier transfer function—that is, the ratio of the output Vo(v) to the input Vi(v).
Figure 1.22 Two examples of STC networks: (a) a low-pass network and (b) a high-pass network.
Figure 1.23 (a) Magnitude and (b) phase response of STC networks of the low-pass type.
Figure 1.24 (a) Magnitude and (b) phase response of STC networks of the high-pass type.
Figure 1.25 Circuit for Example 1.5.
Figure 1.26 Frequency response for (a) a capacitively coupled amplifier, (b) a direct-coupled amplifier, and (c) a tuned or bandpass amplifier.
Figure 1.27 Use of a capacitor to couple amplifier stages.
Figure E1.23
Figure 1.28 A logic inverter operating from a dc supply VDD.
Figure 1.29 Voltage transfer characteristic of an inverter. The VTC is approximated by three straightline segments. Note the four parameters of the VTC (VOH, VOL, VIL, and VIH) and their use in determining the noise margins (NMH and NML).
Figure 1.30 The VTC of an ideal inverter.
Figure 1.31 (a) The simplest implementation of a logic inverter using a voltage-controlled switch; (b) equivalent circuit when vI is low; and (c) equivalent circuit when vI is high. Note that the switch is assumed to close when vI is high.
Figure 1.32 A more elaborate implementation of the logic inverter utilizing two complementary switches. This is the basis of the CMOS inverter studied in Section 4.10.
Figure 1.33 Another inverter implementation utilizing a double-throw switch to steer the constant current IEE to RC1 (when vI is high) or RC2 (when vI is low). This is the basis of the emitter-coupled logic (ECL) studied in Chapters 7 and 11.
Figure 1.34 Example 1.6: (a) The inverter circuit after the switch opens (i.e., for t 0). (b) Waveforms of vI and vO. Observe that the switch is assumed to operate instantaneously. vO rises exponentially, starting at VOL and heading toward VOH .
Figure 1.35 Definitions of propagation delays and transition times of the logic inverter.
Figure P1.6
Figure P1.10
Figure P1.14
Figure P1.15
Figure P1.16
Figure P1.17
Figure P1.18
Figure P1.37
Figure P1.58
Figure P1.63
Figure P1.65
Figure P1.67
Figure P1.68
Figure P1.72
Figure P1.77
Figure P1.79
Table 1.1 The Four Amplifier Types
Vin Vout
Voltage gain (Av) = Vout/Vin
Linear - output is proportional to input
Amplifiers
Current amplifiers current gain (Ai) = Iout/Iin
Power amplifiers power gain (Ap) = Pout/Pin
Amplifiers
Signal Amplification
Distortion
Non-Linear Distortion
Symbols
Gains – Voltage, Power, Current
Decibels
Amplifier Power SuppliesEfficiency
Voltage_Gain Av vo
vi
Power_Gain Ap load_power PL input_power PI
vo io
vI iI
Current_Gain Ai io
iI
Ap Av Ai
Voltage_gain_in_decibels 20 log Av dB
Coltage_gain_in_decibels 20 log Ai dB
Power_gain_in_decibels 10 log Ap dB
Gain in terms of decibels
Typical values of voltage gain, 10, 100, 1000 depending on size of input signal
Decibels often used when dealing with large ranges or multiple stages
Av in decibels (dB) = 20log|Av|
Ai in decibels (dB) = 20log|Ai|
Ap in decibels (dB) = 10log|Ap|
Amplifiers
Av = 10 000 20log|10 000| = 80dBAv = 1000 20log|1000| = 60dBAv = 100 20log|100| = 40dBAv = 10 20log|10| = 20dBAv = -10 20log|-10| = 20dB
Av = 0.1 20log|0.1| = -20dB
Av negative - indicates a phase change (no change in dB)dB negative - indicates signal is attenuated
Amplifiers
Example 1.1
PL 40.5 mW
PI Virms Iirms PI 0.05 mW
Ap
PL
PI Ap 810
W
W
Ap 10 log 810 Ap 29.085 dB
Pdc 10 9.5 10 9.5 Pdc 190 mW
Pdissipated Pdc PI PLPdissipated 149.55 mW
PL
Pdc100 21.316 %
Av9
1 Av 9 Ii 0.0001
Av 20 log 9 Av 19.085 dB
Io9
1000
Io 9 103 A Ai
Io
Ii Ai 90
A
A
Ai 20 log Ai Ai 39.085 dB Vorms9
2 Iorms
9
2
PL Vorms Iorms Virms1
2 Iirms
0.1
2
An amplifier transfer characteristic that is linear except for output saturation.
Amplifiers
Saturation
An amplifier transfer characteristic that is linear except for output saturation.
An amplifier transfer characteristic that shows considerable nonlinearity. (b) To obtain linear operation the amplifier is biased as shown, and the signal amplitude is kept small.
Amplifiers
Non-Linear Transfer Characteristics and Biasing
Circuit model of a voltage amplifier
•EPOLY is a dependent source is SPICE; a voltage controlled voltage source (VCVS)
•EPOLY has a gain of Avo
•The input to EPOLY is the voltage across Ri
Vout = Avo Vin Ri = input resistanceRo = output resistance
+
Vout
-
+
Vin
-
I = 0
Amplifiers
Voltage amplifier with input source and load
What should we design Ro to be?
•Av = Vout/Vin = Avo RL/(RL + Ro)
•Let Ro < < RL to make Av maximum
•Ideally Ro = 0
+
Vout
-
+
Vin
-
•Avo - gain of VCVS only, o indicates output is open
•Av - gain of entire circuit
Av changes with circuit, Avo does not!
Amplifiers
Input resistance of amplifier circuit
+
Vout
-
+
Vin
-
What should we design Rin to be?
•Vin = Vs Ri/(Ri + Rs)
•Let Rin >> Rs to make Vin = Vs
•Ideally Rin = infinity
If Rin = infinity, then all of Vsmakes it to the the amplifier;otherwise part of the signal is lost
Amplifiers
Basic characteristics of ideal amplifier
For maximum voltage transfer
Rout = 0
Rin = infinity
Amplifiers
Amplifiers
Example 1.2
vI 0.6 0.61 0.69
vo vI 10 1011
e40 vI
0.58 0.6 0.62 0.64 0.66 0.68 0.70
5
10
vo vI
vI
vI 0.673vI Find vI
vo 10 1011
e40 vI
givenvo 5
vI 0
Lplus 10Lplus vo 0( )
vo vI 10 1011
e40 vI
vI 0
vI 0.69vI Find vI
vo 10 1011
e40 vI
given
inital valuevI 0vo 0.3
Lminus 0.3
Amplifiers
Example 1.2
Amplifiers
Example 1.2
highlight equation use symbolicsthen differentiate10 10
11e
40 vI
12500000000
exp 40 vI
12500000000
exp 40 0.673( ) 196.457
Circuit Models For Amplifiers
Voltage Amplifiers
Common Models
Show example on board
Circuit Models For Amplifiers
Example 1.3
Class assignment
Circuit Models For Amplifiers
Other Amplifiers
Current
Transconductance
Transresistance
Circuit Models For Amplifiers
Example 1.4
Large-signal equivalent-circuit models of the npn BJT operating in the active mode.
Frequency Response of Amplifiers
Bandwidth
Single-Time Constant Networks
http://www.clarkson.edu/%7Esvoboda/eta/plots/FOC.html
http://www.clarkson.edu/%7Esvoboda/eta/acWorkout/Switched_RCandRL.html
Frequency Response of Amplifiers
Bandwidth
RC Circuits – Class Exercise
(a) Magnitude and (b) phase response of STC networks of the low-pass type.
Frequency Response of Amplifiers
Bandwidth
Frequency Response of Amplifiers
Frequency Response of Amplifiers
Bandwidth
(a) Magnitude and (b) phase response of STC networks of the high-pass type.
Frequency Response of Amplifiers
Frequency Response of Amplifiers
Example 1.5
Class assignment
Frequency Response of Amplifiers
Classification of Amplifiers Based on Frequency Response
Frequency Response of Amplifiers
Exercise 1.6
Class assignment
The Digital Logic Inverter
Function
Transfer Characteristics
Noise Margins
The Digital Logic Inverter
Function
Transfer Characteristics
Noise Margins
The Digital Logic Inverter
Inverter Implementation