Slide 1

Presenter :
Engr. Cezar N. Velasco Jr.


Slide 2

Learning Outcomes
Describe the historical development of
electronics
 Describe the design process of electronic
circuits and systems
 Describe electronic systems and their
classifications



Slide 3

Introduction
Radios
Televisions
Audio equipments
Computers
Industrial Control and
Automation

The field of electronics deals with the design
and applications of electronic devices


Slide 4


Slide 5

History of Electronics
1958
1956
1947

Transistor

1925

Field Effect
device

1906
1904

Triode
vacuum tube

Solid-state
point contact
diode

Thyristor

FM radio,
Radar

First radio
circuits:
Superheterodyne
receiver,
Television

Integrated
Circuits (ICs)
Power
Electronics

Color Television
Unipolar field
effect transistor


Slide 6

Moore’s Law Diagram

Growth in number of Transistors


Slide 7

Levels of Integration
Date

Degree of Integration

Number of Components

1950s

Discrete Components

1 to 2

1960s

Small-scale Integration (SSI)

Fewer than 102

1966

Medium-scale Integration (MSI)

From 102 to 103

1969

Large-scale Integration

From 103 to 104

1975

Very-large-scale Integration

From 104 to 109

1990s

Ultra-large-scale Integration

More than 109

The degree of device integration continues to follow Moore’s
Law, which is an observation made by Gordon E. Moore that the
number of Transistors inside an IC could be doubled every 24
months at a density that also minimizes the cost of a transistor.


Slide 8

Electronic System
An electronic system is an arrangement of electronic
devices and components with a defined set of inputs
and outputs.
Electronic system may be categorized/classified
according to the type of application such as
communication system, medical electronics, instrumentation,
control system, computer system, mechatronics, office electronics,
consumer electronics, automobile electronics


Slide 9

Example of Electronic System
Antenna

Speaker

Electronic
system
Radio receiver

Temperature
sensor

Electronic
system

Display

Temperature display instrument

Electronic systems often use sensors and actuators.
Sensors and actuators are often called transducers.
A loudspeaker is an example of a transducer.


Slide 10

Types of Sensor








Thermistors and thermocouples to measure
temperature
Photransistors and photodiodes to measure light
Strain gauges and piezoelectric materials to
measure force
Potentiometers, inductive sensors, and absolute
position encoders to measure displacement
Microphones to measure sound
Tachogenerators, accelerometers, and Doppler
effect sensors to measure motion
Anemometer to measure the wind speed


Slide 11

Types of Actuators
Resistive heaters to produce heat
 Light-emitting diodes (LEDs) and light
dimmers to control the amount of light
 Solenoids to produce force
 Meters to indicate displacement
 Electric motors to produce motion or speed
 Speakers and ultrasonic transducers to
produce sound.



Slide 12

The field of electronics can be classified
into three areas:
Analog electronics deals primarily with the
operation and applications of transistors as
amplifying devices
 Digital electronics deals primarily with the
operation and applications of transistors as “on”
and “off” switching devices.
 Power electronics deals with the operation and
applications of power semiconductor devices,
including power transistors, as “on” and “off”
for the control and conversion of electric power.



Slide 13

Advantages and disadvantages of Analog
and Digital electronics
Noise is usually present in electronic circuits, added
directly to analog signals and hence affect the signals.
Noise will not affect the digital output and can
effectively removed be removed from digital signals.
 An analog circuit requires fewer individual components
than a digital circuit to perform a given function.
However, an analog circuit often requires large
capacitors or inductors that cannot be manufactured in
ICs.
 A digital circuit tends to be easier to implement than an
analog circuit in ICs, although it can be more complex
than an analog circuit. Digital circuits, however,
generally offer much higher quality and speed of signal
processing.



Slide 14

Advantages and disadvantages of Analog
and Digital electronics
Analog systems are designed to perform specific
functions or operations, whereas digital systems
are adaptable to a variety of tasks or uses.
 Signals from sensors and actuators in electronic
systems are generally analog. If an input signal
has a low magnitude and must be processed at
very high frequencies, then analog technique is
required. For optimal performance and design,
both analog and digital approaches are often
used.



Slide 15

Analog-to-Digital Converters
An A/D converter converts an analog signal to digital form and
provides an interface between analog and digital signals


Slide 16

Digital-to-Analog Converters
A D/A converter takes an input signal in binary form and produces an
output voltage or current in an analog (or continuous) form.


Slide 17

Notation
Definition

Quantity

Subscript

DC value of the signal

Uppercase

Uppercase

VD

AC value of the signal

Lowercase

Lowercase

vd

Total instantaneous value of
Lowercase
the signal (DC and AC)

Uppercase

vD

Complex variable, phasor,
or rms value of the signal

Lowercase

Vd

Uppercase

Example


Slide 18

Example
A

vab

iA

2sinwt
vAB

vAB
VDC

VDC

0
B

VDC and IDC are DC values
vab and ia are the instantaneous AC values
vAB and iA are total instantaneous values
Vab and Ia are total rms values

vab

t


Slide 19

Specifications of Electronic
Systems
An electronic system is normally designed to
perform certain functions or operations. The
performance of an electronic system is specified
or evaluated in terms of voltage , current,
impedance, power, time, and frequency at the
input and output of the system


Slide 20

Transient Specifications
Transient Specifications refer to the output signal of a circuit
generated in response to a specified input signal, usually a
repetitive pulse signal


Slide 21

Cont….Transient Specifications
Delay time td is the time before the circuit can respond to
any input signal.
Rise time tr is the time required for the output to rise from
10% to 90% of its final (high) value.
On time ton is the time during which the circuit is fully turned on
and is functioning in its normal mode.
Fall time tf is the time required for the output to decrease from
90% to 10% of its
initial (high) value.
Off time toff is the time during which the circuit is completely off,
not operating.


Slide 22

Distortion
Distortion may take many forms and can alter the shape,
amplitude, frequency, or phase of a signal


Slide 23

Frequency Specifications
The range of signal frequencies of electronic signals varies widely,
depending on the applications. For frequencies less than fL and greater
than fH, the output is attenuated. But for the frequencies between fL
and fH, the output remains almost constant. The frequency range from
fL to fH is called bandwidth of the circuit


Slide 24

Cont…Frequency Specifications


Slide 25

DC and small-signal Specifications
The DC and small-signal specifications include the
DC power supply VCC , DC biasing currents (required to
activate and operate internal transistor), and power
dissipation PD (power requirement from the DC power
supply).


Slide 26

Signal Amplification Types are classified by
the types of input and output signals







Voltage Amplifier produces an amplified output
voltage in response to an input voltage signal
Transconductance amplifier produces an amplified
output current in response to an input voltage signal
Current Amplifier produces an amplified output
current in response to an input current signal
Impedance amplifier produces an amplified output
voltage and delivers power to a low resistance load
signal
Power amplifier produces amplified output voltage
and deliver power to a low resistance load in
response to an input voltage signal


Slide 27

Functional types are classified by their
function or output characteristics









Linear amplifier produces an output signal in response to an
input signal without introducing significant distortion on the
output signal, whereas a nonlinear amplifier does introduce
distortion.
Audio amplifier is a power amplifier in the audio frequency
(AF) range.
Operational amplifier performs some mathematical functions
for instruments and for signal processing.
Wideband amplifier amplifies an input signal over a wide
range of frequencies to boost signal levels, whereas a
narrowband amplifier amplifies a signal over a specific narrow
range of frequencies.
Radio frequency (RF) amplifier amplifies a signal for use over
the RF range.
Servo amplifier uses a feedback loop to control the output at
the desired level.


Slide 28

Interstage coupling types are classified by the
coupling method of the signal at the input, at
the output, or between stages
RC-coupled amplifier uses a network of resistors and
capacitors to connect it to the following and preceding
amplifier stages.
 LC-coupled amplifier uses a network of inductors and
capacitors to connect it to the following and preceding
amplifier stages.
 Transformer-coupled amplifier uses transformer to match
impedances to the load side and input side.
 Direct-coupled amplifier uses no interstage elements, and
each stage is connected directly to the following and
preceding amplifier stages.



Slide 29

Frequency types are classified in accordance to
the frequency range





DC amplifier is capable of amplifying signals from zero
frequency (DC) and above.
AF amplifier is capable of amplifying signals from 20
Hz to 20 kHz.
Video amplifier is capable of amplying signals up to a
few hundred megahertz (< 10 MHz for TV).
Ultra-high frequency (UHF) amplifier is capable of
amplifying signals up to a few gigahertz.


Slide 30

Load types are classified in accordance to the
type of load




Audio amplifier has an audio type of load
Video amplifier has a video type of load
Tuned amplifier amplifies a single RF or band of
frequencies.


Slide 31

Engineering Design
Engineering design is the process of devising a system,
component, or process to meet desired needs. It is a
decision making process (often iterative), in which the basic
sciences and mathematics and engineering sciences are
applied to convert resources optimally to meet these stated
needs.
Source:
From the definition of ABET (Accreditation Board for
Engineering and Technology)


Slide 32

Analysis is the process of finding the unique specifications or
properties of a given circuit.
Design is the creative process of developing a solution to a
problem.

Elements of Design Process


Slide 33

Circuit-level Design Process


Slide 34

End of first Topic