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Presenter : Engr. Cezar N. Velasco Jr. Introduction to Electronic Circuits and Devices. Learning Outcomes. Describe the historical development of electronics Describe the design process of electronic circuits and systems Describe electronic systems and their classifications. Introduction. - PowerPoint PPT Presentation
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INTRODUCTION TO
ELECTRONIC CIRCUITS AND DEVICES
Presenter :Engr. Cezar N. Velasco Jr.
Learning Outcomes
Describe the historical development of electronics
Describe the design process of electronic circuits and systems
Describe electronic systems and their classifications
Introduction
The field of electronics deals with the design and applications of electronic devices
RadiosTelevisionsAudio equipmentsComputersIndustrial Control and Automation
History of Electronics 1958
1956
1947
1925
1906
1904
Triode vacuum
tube
Solid-state point
contact diode
Field Effect device
First radio circuits:Superheterodyne receiver,Television
Transistor
FM radio,Radar
Thyristor
Integrated Circuits
(ICs)
Color Television
Unipolar field effect
transistor
Power Electroni
cs
Moore’s Law Diagram
Growth in number of Transistors
Levels of IntegrationDate 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.
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
Example of Electronic System
Electronic systems often use sensors and actuators. Sensors and actuators are often called transducers.A loudspeaker is an example of a transducer.
Electronic system
Radio receiver
AntennaSpeaker
Electronic system
DisplayTemperatur
esensor
Temperature display instrument
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
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.
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.
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.
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.
Analog-to-Digital Converters
An A/D converter converts an analog signal to digital form and provides an interface between analog and digital signals
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.
Notation
Definition Quantity Subscript Example
DC value of the signalUppercase
Uppercase
VD
AC value of the signalLowercase
Lowercase
vd
Total instantaneous value of the signal (DC and AC)
Lowercase
Uppercase
vD
Complex variable, phasor, or rms value of the signal
Uppercase
Lowercase
Vd
Example
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
B
A
vAB
VDC
iA vAB
t
VDC
vab
0
2sinwt
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
Transient SpecificationsTransient Specifications refer to the output signal of a circuit generated in response to a specified input signal, usually a repetitive pulse signal
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.
DistortionDistortion may take many forms and can alter the shape, amplitude, frequency, or phase of a signal
Frequency SpecificationsThe 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
Cont…Frequency Specifications
DC and small-signal SpecificationsThe 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).
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
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.
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.
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.
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.
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)
Elements of Design Process
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.
Circuit-level Design Process
End of first Topic