Linear integrated circuits intro

8/11/2019 Linear integrated circuits intro

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INTRODUCTION TOLINEAR INTEGRATED

CIRCUITS


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Digital Vs Analog

Digital signals can convey information with greaternoise immunity.

Digital signals can be processed by digital circuitcomponents, which are cheap and easilyproduced in many components on a single chip.

Digital signals typically use less bandwidth.

Digital is more secure, It is also easier to translate

human audio and video signals and othermessages into machine language.

Enables transmission of signals over a longdistance.


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Digital Vs Analog

But why Analog? Everything we see hear and perceive in life is analog

e.g., voice, music, visual perception, seismic activity,energy delivery etc.

As a result all electronic must interface with the worldvia analog electronics.

Examples of the types of applications the field enjoysrange from biologically inspired (e.g., pacemakers,nanotechnology products) and commercial products

(e.g., laptops , cellular phones, micro sensors) tomilitary(e.g., unmanned aerial vehicles, light weightelectronic equipment)

It is therefore impossible to imagine engineering real-life solutions without the help and support of highperformance analog electronics.


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Operational amplifier

In this subject the main components of linear ICdesign are dealt.

The operational amplifier is one of the most usefuland important components of analog electronics.They are widely used in popular electronics. It has

infinite open-loop gain.

Infinite input impedance Rin, and so zero inputcurrent.

Zero input offset voltage.

Infinite voltage range available at the output.

Infinite bandwidth with zero phase shift and infiniteslew rate.


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Operational amplifier

Due to its characteristics it is used to design

Filters

Amplifiers

Oscillators Comparators

Integrators and differentiators

Opamp has three stages

A differential amplifier with high voltage gainA single-pole low-pass filter frequency

An output buffer (unity gain).


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Differential amplifier

Differential amplifiers offer many advantages formanipulating differential signals.

They provide immunity to external noise; a 6-dBincrease in dynamic range, which is a clear advantage

for low-voltage systems and reduced second-orderharmonics.

They provide an easy means of anti alias filtering, anda dedicated input easily sets the required common-mode voltage.

These amplifiers are also well-suited for drivingdifferential transmission lines, and active terminationprovides for increased efficiency. You can easily adaptinverting-amplifier topologies to fully differentialamplifiers by implementing two symmetric feedback

paths.


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555 timer

The 555 timer was created by Hans Camenzind (b. 1934) in1970 while he was working for Signetics. The design processtook about a year. Designing the chip was all done by hand,using rubylith which made the process take much longer thanby today's standards.

The 555 timer replaced 23 transistors, 15 resistors and 2diodes and allowed manufacturers to use this problemsolving method much easier. Today with billions of the chipsin existence, it is one of the most widely used chips.

It is the gateway drug to the world of integrated circuits.

Frequently, the 555 is used in astable mode to generate acontinuous series of pulses, but you can also use the 555 tomake a one-shot or monostable circuit.

The 555 can source or sink 200 mA of output current, and iscapable of driving wide range of output devices.


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PLL

A phase-locked loop (PLL) is an electronic circuit with a voltage- orcurrent-driven oscillator that is constantly adjusted to matchin phase (and thus lock on) the frequency of an input signal. Inaddition to stabilizing a particular communications channel (keepingit set to a particular frequency)

A PLL can be used to generate a signal, modulate or demodulate asignal, reconstitute a signal with less noise, or multiply or divide afrequency. PLLs are frequently used in wireless communication,particularly where signals are carried using frequency modulation(FM) or phase modulation (PM). PLLs can also be used inamplitude modulation (AM).

PLLs are more commonly used for digital data transmission, but can

also be designed for analog information. Phase-locked loop devicesare more commonly manufactured as integrated circuits (ICs)although discrete circuits are used for microwave.

Applications of PLL are frequency multiplication, frequencytranslation, AM, FM & FSK demodulators


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ADC and DAC

Analog to Digital Converter (ADC) and Digital toAnalog Converter (DAC) are very importantcomponents in electronic equipment.

Since most real world signals are analog, these two

converting interfaces are necessary to allow digitalelectronic equipments to process the analog signals.

Take the audio signal processing, ADC converts theanalog signal collected by audio input equipment, suchas a microphone, into a digital signal that can be

processed by computer. The computer may add sound effect such as echo and

adjust the tempo and pitch of the music. DAC convertsthe processed digital signal back into the analog signalthat is used by audio output equipment such as a

speaker.


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Types of DACs

weighted resistor DAC

R-2R ladder DAC

inverted R-2R DAC IC 1408 DAC

Types of ADCs

parallel comparator type ADC

counter type ADC successive approximation ADC

dual slope ADC


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Modulators and multipliers

A modulator is a circuit with multiple inputs whereone input can modify or control the signal flowfrom another input to the output

A multiplier has two analog inputs and an output

proportional to the product of the two amplitudes Topics covered are Four Quadrant multiplier

balanced modulator

IC1496,Applications of analog switches Multiplexers

Sample & Hold amplifiers.


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THANK YOU

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Linear integrated circuits intro