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8/9/2019 LIC 2m With Answer

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Linear Integrated Circuits and Applications

Two marks questions & answers

UNIT I – IC FABRICATIN

1.Define an Integrated circuit.

An integrated circuit(IC) is a miniature, low cost electronic circuit consisting ofactive and passive components fabricated together on a single crystal of silicon. heactive components are transistors and diodes and passive components are resistors andcapacitors.

!."hat are the basic processes involved in fabricating ICs using planar technology#

1.$ilicon wafer (substrate) preparation %.&hotolithography '.Isolation techniue!.pita*ial growth +.Diffusion .-etalliation

/.0*idation .Ion implantation2.Assembly processing 3 pac4aging

/.5ist out the steps used in the preparation of $i 6 wafers.

1.Crystal growth 3doping %."afer policing 3 etching!.Ingot trimming 3 grinding +."afer cleaning/.Ingot slicing

%. "rite the basic chemical reaction in the epita*ial growth process of pure silicon.

he basic chemical reaction in the epita*ial growth process of pure siliconis the hydrogen reduction of silicon tetrachloride. 1!77C $iCl% 8 !9! :; $i 8 %

9Cl

+. "hat are the two important properties of $i0!#

1.$i0! is an e*tremely hard protective coatng 3 is unaffected by almost all reagentse*cept by hydrochloric acid. hus it stands against any contamination.

!.


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'. "hat is meant by molecular beam epita*y(-


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5ithography is a process bywhich the pattern appearing on the mas4 is transfered to thewafer.It involves two steps the first step reuires applying a few drops of photoresist to thesurface of the wafer 3 the second step is spinning the surface to get an even coating of the

photoresist across the surface of the wafer.

12."hat are the different types of lithography# "hat is optical lithography#

he different types of lithography are 1.&hotolithography!.lectron beam lithography/. ray beam lithography%.Ion beam lithographyptical lit%ograp%

E 0ptical lithography comprises the formation images with visible or => radiation ina photoresist using contact, pro*imity or proFection printing.

13."hat are the two processes involved in photolithography#

a) -a4ing a photographic mas4 b) &hoto etching

he development of photographic mas4 involves the preparation of initial artwor4 and its reduction , decomposition of initial artwor4 or layout into several mas4 layers.&hoto etching is used for the removal of $i0! from desired regions so that the desiredimpurities can be diffused.

1%. Distinguish between dry etching 3 wet etching.

Dry etching Gaseous mi*ture is used as the chemical reagent. Chemicalreagents used are in the liuid form.

"et etchingIt produces straight walled etching process. It produces patterns with undercutting.

1+. "hat is meant by reactive plasma etching#

he term reactive plasma is meant to describe a discharge in which ioniation 3fragmentation of gases ta4es place3 produce chemically active plasma species,freuently o*idiers and reducing agents. $uch plasmas are reactive both in the gas

phase 3 with solid surfaces e*posed to them. "hen these interactions are used to formvolatile products so that material is removed or etching of material form surfaces that arenot mas4ed to form lithographic patterns, the techniue is 4nown as reactive plasmaetching.

1. "hat is isotropic 3 anisotropic etching processes#

Isotropic etching is a wet etching process which involves undercutting.Aisotropic etching is a dry etching process which provides straight walled patterns.

1'. Define diffusion.

he process of introducing impurities into selected regions of a silicon wafer is


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called diffusion. he rate at which various impurities diffuse into the silicon will be of the order of 1 &range of 277oC to 1177oC he impurity atoms have the tendency tomove from regions of higher concentrations to lower concentrations.

1. "hat is dielectric isolation#

In dielectric isolation, a layer of solid dielectric such as $i0! or rubycompletely surrounds each components thereby producing isolation, both electrical 3

physical. his isolating dielectric layer is thic4 enough so that its associatedcapacitance is negligible. Also, it is possible to fabricate both pnp 3 npn transistorswithin the same silicon substrate.

12. "hat is metalliation#

he process of producing a thin metal film layer that will serve to ma4einterconnection of the various components on the chip is called metalliation.

!7. "hat are the advantages of ion implantation techniue#

• It is performed at low temperature. herefore, previously diffused regions have a

lesser tendency for lateral spreading.• In diffusion process, temperature has to be controlled over a large area inside the

oven, whereas in ion implantation process, accelerating potential 3 beam contentare dielectrically controlled from outside.

UNIT II'C(ARACT)RI!TIC! F *'A+*

1."hat are the advantages of ICs over discrete circuits#

• Improved functional performance.• -inimiation 3 hence increased euipment density.• -atched devices.• Cost reduction due to batch processing.• Increased operating speeds• Increased system reliability• Heduction in power consumption

!. "hat is 0&A-

An operational amplifier is a direct coupled high gain amplifier consisting of oneor more differential amplifiers, followed by a level translator and an output stage. It is aversatile device that can be used to amplify ac as well as dc input signals 3 designed for

computing mathematical functions such as addition, subtraction, multiplication,integration and differentiation.

/. Draw the pin configuration of IC'%1.


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%. 5ist out the ideal characteristics of 0&A- (i ) 0pen loop gain infinite

(ii) Input impedance infinite

(iii) 0utput impedance low

(iv) oJ7 when >1J>!J7

5."hat are the different 4inds of pac4ages of IC'%1#a) -etal can (0) pac4age

b) Dual?in?line pac4agec) @lat pac4age or flat pac4

6."hat are the assumptions made from ideal op?amp characteristics#

• he current drawn by either of the input terminals (non? invertingKinverting) is negligible.

• he potential difference between the inverting 3 non?inverting input terminals

is ero.

'. -ention some of the linear applications of op 6 amp#

Adder, subtractor, voltage to current converter, current to voltage converters,

instrumentation amplifier, analog computation, power amplifier, etc are some of thelinear op?amp circuits.

. -ention some of the non 6 linear applications of op?amps#

Hectifier, pea4 detector, clipper, clamper, sample and hold circuit, log amplifier,anti 6log amplifier, multiplier are some of the non 6 linear op?amp circuits.

2. "hat are the areas of application of non?linear op? amp circuits#

1. Industrial instrumentation

2.Communication3.$ignal processing

17. "hat happens when the common terminal of >8 and >? sources is not grounded#

If the common point of the two supplies is not grounded, twice the supply voltagewill get applied and it may damage the op?amp.


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11. Define input offset voltage#

A small voltage applied to the input terminals to ma4e the output voltage as erowhen the two input terminals are grounded is called input offset voltage.

1!. Define input offset current. $tate the reasons for the offset currents at the input of the op?amp#

he difference between the bias currents at the input terminals of the op?amp iscalled as input offset current. he input terminals conduct a small value of dc current to

bias the input transistors. $ince the input transistors cannot be made identical, there e*istsa difference in bias currents.

1/. Define C-HH of an op?amp#

It is defined as the ratio of the differential voltage gain tocommon mode voltage gain. C-HHJ L J AdKAc

1%. In practical op?amps, what is the effect of high freuency on its performance#

he open?loop gain of op?amp decreases at higher freuencies due to the presenceof parasitic capacitance. he closed?loop gain increases at higher freuencies and leads toinstability.

1+. "hat is the need for freuency compensation in practical op?amps#

@reuency compensation is needed when large bandwidth and lower closed loop gainis desired. Compensating networ4s are used to control the phase shift and hence to improvethe stability.

16.-ention the freuency compensation methods.

1. Dominant?pole compensation

2. &ole?ero compensation.

17."hat are the merits and demerits of Dominant?pole compensation#

1. oise immunity of the system is improved.

2. 0pen?loop bandwidth is reduced.

18.Define slew rate.

he slew rate is defined as the ma*imum rate of change of output voltage caused by a step input voltage. An ideal slew rate is infinite which means that op?ampBs outputvoltage should change instantaneously in response to input step voltage.

12. "hy IC '%1 is not used for high freuency applications#

IC'%1 has a low slew rate because of the predominance of capacitance present inthe circuit at higher freuencies. As freuency increases the output gets distorted due tolimited slew rate.

!7. "hat causes slew rate#


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here is a capacitor with?in or outside of an op?amp to prevent oscillation. It is thiscapacitor which prevents the output voltage from responding immediately to a fastchanging input.

!1. Define thermal drift.

he bias current, offset current 3 offset voltage change with temperature. A circuitcarefully nulled at !+oC may not remain so when the temperature raises to /+ oC. his iscalled thermal drift. 0ften, offset current drift is e*pressed in nAK oC and offset voltagedrift in m>K oC.

!!. Define supply voltage reFection ratio ($>HH)#

he change in 0&A-&Bs input offset voltage due to variations in supply voltage iscalled the supply voltage reFection ratio. It is also called &ower $upply HeFection Hatio(&$HH) or &ower $upply $ensitivity (&$$).

!/. "hat are the basic reuirements of the input stage of 0p?amp#

• 9igh voltage gain.• $mall input offset voltage.• 9igh input impedance• $mall input offset current.• wo input terminals.• 9igh C-HH.• 5ow input bias current

!%. "hat are the basic reuirements of the output stage of 0p?amp#

• 5arge output voltage swing capability.• 5ow uiescent power dissipation.• 5arge output current swing capability.• $hort circuit protection• 5ow output impedance.

!+. Define Differential gain#

he gain with which differential amplifier amplifies the difference between twoinput signals, is called differential gain (Ad).

Ad J >7 K >d

!. Define Common -ode Gain#

he gain with which differential amplifier amplifies the common mode signal to produce the output is called common mode gain.

AC J >0 K >C

!'. Define Common -ode $ignal.


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he average level of two input signals is called common mode signal (>C).

>C J (>1 8 >!) K !

!. "hat are the features of Differential amplifier#

• 9igh differential voltage gain.

• 9igh input impedance.

• 5ow common mode gain.

• 5arge band width.• 9igh C-HH.

• 5ow output impedance.

• wo input terminals.

• 5ow offset voltages and currents

!2. "hat are the D.C Characteristics of 0p?amp#

• Input oltage series feed bac4.• >oltage shunt feedbac4.• Current series feedbac4.• Current shunt feedbac4.

/!. "hat are the advantages of negative feedbac4#

1. It reduces the gain and ma4es it controllable

2. It increases the bandwidth i.e freuency range

3. It increases the input resistance of the op?amp.


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4. It decreases the output resistance of the op amp.5. It reduces the possibility of distortion.

33."hat are the classification of opamp ICs based on temperature ranges#

1. -ilitary temperature range ?++ 0 C to 6 1!+ 0 C.2. Industrial temperature range ? !7 o C to 8 + 0 C.

3. Commercial temperature range 70

C to '70

C.34."hat are the features of IC '%1#

• o freuency compensation reuired.• o latch up.• $hort circuit protection provided.• 5arge common mode and differential voltage range.• 0ffset voltage null capability.

35. Define voltage follower.

A circuit in which the output voltage follows the input voltage is calledvoltage follower circuit. >0 J > in

36. "hat are the advantages of voltage follower#

• >ery large input resistance, of the order of mega ohms.

• 5ow output impedance, almost ero. 9ence it can be used to connecthigh impedance source to a low impedance load as a buffer.

• It has large band width.

• he output follows the input e*actly without phase shift.

/'. "hat is meant by integrator#

In an integrator circuit, the output voltage is the integration of the input voltage.he integrator circuit using active devices li4e op?amp is called active integrator. heintegrator circuit can be obtained without using active devices li4e op amp, transistors iscalled passive integrator.

/. "rite the applications of &ractical Integrator.

• In the analog computers.

• In analog to digital converters.• In solving the differential euations.

• In ramp generators.

/2. "hat is meant by differentiator#

he circuit which produces the differentiation of the input voltage at its output iscalled differentiator. he circuit using active devices li4e op?amp is called active


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differentiator. he circuit can be obtained without using active devices li4e op amp,transistors is called passive differentiator.

%7. "rite the applications of &ractical differentiator.

• In the wave shaping circuits to detect the high freuency components in the input

signal.

• As a rate? of?change detector in the @- demodulation.

UNIT III ' A**LICATIN! F * A+*

1. "hat is the need for an instrumentation amplifier#

In a number of industrial and consumer applications, the measurement of physicaluantities is usually done with the help of transducers. he output of transducer has to beamplified $o that it can drive the indicator or display system. his function is performed

by an instrumentation amplifier.

!. 5ist the features of instrumentation amplifier

• high gain accuracy• high C-HH

• high gain stability with low temperature co?efficient• low dc offset

• low output impedance

/. "hat is a comparator#

A comparator is a circuit which compares a signal voltage applied at one input of anopamp with a 4nown reference voltage at the other input. It is an open loop op ? amp withoutput 8 >sat.

4."hat are the applications of comparator#• ero crossing detectors

• "indow detector

• ime mar4er generator

• &hase detector.

5."hat is a $chmitt trigger#

$chmitt trigger is a regenerative comparator. It converts sinusoidal input into a suarewave output. he output of $chmitt trigger swings between upper and lower threshold

voltages, which are the reference voltages of the input waveform.

. "hat is a multivibrator#

-ultivibrators are a group of regenerative circuits that are used e*tensively intiming applications. It is a wave shaping circuit which gives symmetric or asymmetricsuare output. It has two states stable or uasi? stable depending on the type ofmultivibrator.


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'. "hat do you mean by monostable multivibrator#

-onostable multivibrator is one which generates a single pulse of specified

duration in response to each e*ternal trigger signal. It has only one stable state

Application of a trigger causes a change to the uasi?stable state. An e*ternal trigger

signal generated due to charging and discharging of the capacitor produces the transition

to the original stable state.

. "hat is an astable multivibrator#

Astable multivibrator is a free running oscillator having two uasi?stable states.hus, there are oscillations between these two states and no e*ternal signal is reuired to

produce the change in state.

2. "hat is a bistable multivibrator#


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15."hat is integrating type converter#

An ADC converter that perform conversion in an indirect manner by first changingthe analog IK& signal to a linear function of time or freuency and then to a digital code is4nown as integrating type AKD converter.

1. *plain in brief the principle of operation of successive Appro*imation ADC.

he circuit of successive appro*imation ADC consists of a successiveappro*imation register ($AH), to find the reuired value of each bit by trial 3 error. "iththe arrival of $AH command, $AH sets the -$< bit to 1. he 0K& is converted into ananalog signal 3 it is compared with IK& signal. his 0K& is low or high. his processcontinues until all bits are chec4ed.

1'. "hat are the main advantages of integrating type ADCs#

i. he integrating type of ADCBs doing not need a sampleK9old circuit at the input.ii. It is possible to transmit freuency even in noisy environment or in an isolated

1. Define conversion time.

It is defined as the total time reuired converting an analog signal into itsdigital output. It depends on the conversion techniue used 3 the propagationdelay of circuit components. he conversion time of a successive appro*imationtype ADC is given by (n81) "here ???cloc4 period c???conversion time n? no.of bits.

12. Define resolution of a data converter.

he resolution of a converter is the smallest change in voltage which may be produced at the output or input of the converter.

Hesolution (in volts) J >@$K!n?1J1 5$< increment. he resolution of an ADCis defined as the smallest change in analog input for a one?bit change at the output.

!7. *plain in brief stability of a converter.

he performance of converter changes with temperature age 3 power supplyvariation. $o all the relevant parameters such as offset, gain, linearity error 3monotonicity must be specified over the full temperature 3 power supply ranges to have

better stability performances.

!1. "hat is meant by linearity#

he linearity of an ADCKDAC is an important measure of its accuracy 3 tells ushow close the converter output is to its ideal transfer characteristics. he linearity error isusually e*pressed as a fraction of 5$< increment or percentage of full?scale voltage. A


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good converter e*hibits a linearity error of less than MN5$


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A filter is a circuit that is designed to pass a specified band of freuencies whileattenuating all the signals outside that band. It is a freuency selective circuit.

29."hat are the types of >KI converter.

1. @loating type.

2. Grounded type.

30."rite the applications of >?I Converter.• 5ow >oltage D.C >oltmeter.

• ener diode tester

• 5ow >oltage A.C >oltmeter.

• Diode tester and -atch filter.

31. "rite the applications of I?> Converter.

• &hoto diode detector.

• &hoto @ Detector.

32."hat are the types of comparator#• Inverting comparator.

• on inverting comparator.

//. "rite the advantages of HC phase shift oscillator.

• he circuit is simple to design.

• Can produce output over audio freuency range.

• &roduces sinusoidal output wave form.

• It is a fi*ed freuency oscillator.


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/%. "rite the advantages of "ein bridge oscillator.

• arying the two capacitor values simultaneously, by mounting themon the common shaft, different freuency ranges can be obtained.

• It is useful audio freuency range i.e. !7 9 to 177 9.• he perfect sine wave output is possible.

/+. "hat is meant by clipper#

he circuits which are used to clip off the unwanted portions of the input voltageabove or below certain levels, so as to produce limited reuired output are called limitingcircuits. As some part of input gets clipped off to produce output, these circuits arecommonly called clipping circuits.

/. "hat is meant by clamper circuits#

he circuits which are used to add a d.c. level as per the reuirement, to the a.c.output are called as clamper circuits. It is also called as d.c. restorer circuits.

/'. "hat are the types of clipper circuits#

• &ositive clipper circuits? remove some positive part from the input it produce

output.

• egative clipper circuits? remove some negative part from the input it produce

/. "hat are the types of clamper circuits#

• &ositive clamper circuits?he clamped d.c. level is positive.

• egative clamper circuits? he clamped d.c. level is negative.

UNIT I,'!*)CIAL ICs

1."hat are the basic elements 0@ IC+++ timer#• Hela*ation oscillator • H?$ flipflop

• wo comparator• Discharge transistor.

!.*plain the function of pin! in IC+++ timer#

he pin ! is trigger pin.he inverting input of comparator ! is brought out astrigger.it is compared with 1K/>cc 3 when it is below this level,the output of thecomparator ! goes high which is given to reset input of H?$ flip flop.

/. *plain the function of pin + in IC+++ timer#

his pin is inverting input of the comparator 1.he voltage divider holds thevoltage of this pin at !K/>cc.his is the reference level for the comparator 1 with whichthe threshold is compared.$o generally e*ternal control voltage at pin + is not used.0nlywhen the reference reuired is other than !K/>cc for the comparator 1 then it is used.


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%. *plain the function of pin in IC+++ timer.

his is the threshold pin which is the noninverting input of the comparator 1.hee*ternal voltage is applied to this pin which is compared with !K/>cc .If this is more than!K/>cc then comparator output goes high which is used to set the H?$ flipflop.hisma4es the outpit at pin / low.

+."hy >C0 is called voltage to freuency converter#he >C0 provides the linear relationship between the applied voltage 3 the

output freuency.$o it is 4nown as voltage to freuency converter.

."hich parameter decides the pullin time#

Initial phase 3 freuency difference between the two signals. 0verall loop gain.


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Dual in line pac4age 3 @lat pac4age.

12.$tate any % applications of monostable circuit using IC +++.

• @reuency doubler

• &ulse width modulation

• 5inear ramp generator

• -issing pulse detector.

13. $tate the e*pressions for the duty cycle 3 the freuency of oscillations forastable circuit using IC +++#

D J (HA8HC0 P>J @7K(8>)

1."hat are the filters used in &55#• 5oop filter• $ideband filter.

12."hat is the use of loop filter#

I controls the fundamental loop characteristic such as loop bandwidth,loc4ingtime 3 transient response by establishing values for the loop natural freuency 3 thedamping factor.


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!7. "hat is the use of $ideband filter#

It provides additional filtering of the error signal to generate a stable 3 cleancontrol voltage to the >C0.It provides attenuation to the sideband s that are created dueto disturbances on line.

!1."hat is @$P techniue#

In digital data communication ,binary code is transmitted by shifting a carrierfreuency between two preset freuencies.

!!.9ow pulse position modulator can be obtained using +++ timer#It is constructed by applying a modulating signal to pin + of a +++ timer connected

for astable operation.

!/. "hat are the applications of +++ imer#

• astable multivibrator• monostable multivibrator• -issing pulse detector• 5inear ramp generator• @reuency divider• &ulse width modulation• @$P generator

• &ulse position modulator• $chmitt trigger

!%. 5ist the applications of +++ timer in monostable mode of operation

missing pulse detector 5inear ramp generator @reuency divider &ulse width modulation.

25.5ist the applications of +++ timer in Astable mode of operation#• @$P generator • &ulse?position modulator

26.Define +++ IC#

he +++ timer is an integrated circuit specifically designed to perform signalgeneration and timing functions.


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27.5ist the basic bloc4s of IC +++ timer#• A rela*ation oscillator• H$ flip flop

• wo comparator • Discharge transistor.

28.5ist the features of +++ imer#It has two basic operating modes monostable and astble

It is available in three pac4ages. pin metal can , pin dip, 1% pin dip. It has very hightemperature stability.

!2. Define duty cycle#

he ratio of high output and low output period is given by a mathematical parameter called duty cycle. It is defined as the ratio of 0 ime to total time.

/7. Define >C0.

A voltage controlled oscillator is an oscillator circuit in which the freuencyof oscillations can be controlled by an e*ternally applied voltage.

31. 5ist the features of + >C0#

• "ide supply voltage range(17?!%>)

• >ery linear modulationCharacteristics

• 9igh temperature stability

/!. "hat does u mean by &55#

A &55 is a basically a closed loop system designed to loc4 output freuency and phase to the freuency and phase of an input signal.

//. Define loc4 range#

"hen &55 is in loc4, it can trap fre changes in the incoming signal. he rangeof freuencies over which the &55 can maintain loc4 with the incoming signal iscalled as loc4 range.

/%. Define capture range#

he range of freuencies over which the &55 can acuire loc4 with the inputsignal is called as capture range.

/+. Define pull?in time#he total time ta4en by the &55 to establish loc4 is called pull?in time.

36.5ist the applications of ++ &55.


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• @reuency multiplier

• @reuency synthesier

• @- detector

37."hat are the two types of analog multiplier Ics#a) IC AD +//

b) IC AD +/%

38."hat is ICAD +//#

It is a multiplier IC by analog devices. It is a low cost IC comprising a transconductancemultiplying element, stable reference and an output amplifier.

39.5ist the features of ICAD+//#• Its operation is very simple.

• 0nly % e*ternal adFustments are necessary• -a*imum % uadrant error is below 7.+R

40."hat is ICAD +/%#It is a multiplier IC by analog devices. It is the first general purpose multiplier capable of

providing gain upto 177.

UNIT ,'A**LICATIN! F ICs

1."hat are the components of a basic voltage regulator#

• >oltage reference

• rror amplifier

• @eedbac4 networ4.

• Active series or shunt control element.

!."hat are the advantages of IC voltage regulators#(i) asy to use.(ii) It greatly simplifies power supply design. (iii) Due to mass production ,low in cost.

(iv) versatile.

(v) =sed for local regulation.

/.$tate some important features of IC '!/(i) Input 3 output short circuit protection is provided.


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(ii) It has good line 3 load regulation. (iii) 5ow standby current drain. (iv) $maller sie,lower cost.(v) low temperature drift 3 high ripple reFection.

%."hat are the important bloc4s of IC '!/

(i) emperature compensated voltage reference source.(ii) An opamp circuit used as an error amplifier.

(iii) A series pass transistor capable of 1+7mA output current.(iv) ransistor used to limit output current.

+.$tate any three applications of IC'!/

• to %7>.

• &ea4 currents to 1.+A without e*ternal transistors.

• 5ow standby current drain.

1!.9ow the current boosting is achieved in a IC '!/ #


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he ma*imum load current of IC '!/ is 1+7mA .If the current is to be boosted

then e*ternal resistor T1 is connected to the output terminal.

1/.-ention some switched capacitor filter ICBs.• -@+?=niversal second order filter• -@?=nity gain si*th order butterworth 5& filter.• -@?wo second order


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!1. "hat is a switching regulator#

$witching regulators are those which operate the power transistor as a highfreuency onKoff switch, so that the power transistor does not conduct currentcontinously.his give improved efficiency over series regulators.

!!. "hat are the advantages of IC voltage regulators# .

•

5ow cost• high reliability

• reduction in sie

• e*cellent performance

23.Give some e*amples of monolithic IC voltage regulators#• ' series fi*ed output, positive voltage regulators• '2 series fi*ed output, negative voltage regulators

• general purpose regulator.

24."hat is the purpose of having input and output capacitors in three terminal IC regulators#

A capacitor connected between the input terminal and ground cancels theinductive effects due to long distribution leads. he output capacitor improves thetransient response.

!+. Define line regulation#

5ine regulation is defined as the percentage change in the output voltage for a

change in the input voltage. It is e*pressed in millivolts or as a percentage of the output

voltage.

!. Define load regulation.5oad regulation is defined as the change in output voltage for a change in load

current. It is e*pressed in mill volts or as a percentage of the output voltage.

!'. "hat is meant by current limiting#Current limiting refers to the ability of a regulator to prevent the load current from

increasing above a preset value.

!. Give the drawbac4s of linear regulators#

he input step down transformer is bul4y and e*pensive because of low linefreuency.


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!2. "hat is the advantage of switching regulators#

Greater efficiency is achieved as the power transistor is made to operate as lowimpedance switch. &ower transmitted across the transistor is in discrete pulses rather than as a steady current flow.


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/."hat are the features of -A's%7#• $tep up,• $tep down or inverting operation• 0peration from !.+ to %7 >.• 7Db line and load regulation.

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