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CHAPTER1Hans Oersted Relationship of magnetism and electricity that served as the
foundation of theory for electromagnets
Most important electrical effect is the magnetic effect
Michael Faraday Theory of electromagnetic inductionCurrent Carrying conductor would move when placed in a
magnetic field
James Maxwell Electromagnetic Theory of lightAndre Ampere Demonstrated that there are magnetic effects around every
current carrying conductor and that these conductors act like a
magnet
Kamerlingh Onnes SuperconductivityFaradays Law Whenever a conductor cuts a magnetic flux, an emf is induced
in itFaradays 1st Law The magnitude of induced emf is directly proportional to therate of change of flux linkages
Faradays 2nd Law Whenever the flux linking a coil or current changes, an emf isinduced in it
Coulumbs 1st Law Force between 2 magnetic poles is directly proportional to theirstrengths
Coulumbs 2nd Law Force between 2 magnetic poles id inversely proportional to thedistance between them
Childs Law Current in a thermionic diode varies directly with the threehalves power of anode voltage and inversely with the square of
distance between the electrodes
Wiedmann-FranzLaw
Ratio of the thermal conductivity to the electric conductivity is
directly proportional to the absolute temp for all metals
Curies Law The magnetic susceptibilities of most paramagnetic materialsare inversely proportional to their absolute temperatures
Curie-Weiss Law Law relating the M and E susceptibilities and the absolutetemperature
Ewings theory ofFerromagnetism
Theory of ferromagnetic phenomena which assumes each atom
is a permanent magnet which can turn freely about its center
under the influence of applied fields and magnets
Amperes Theorem States that a current flowing in a circuit produces a magneticfield at external points equivalent to that due to a magnetic
shell whose bounding edge is the conductor and whose
strength is equal to the strength of current
Right hand rule Also called corkscrew ruleEnd Rule If looking at any one end of a solenoid, the direction of current
is found to be clockwise then the end under observation is a
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south pole
Helix Rule If a solenoid is held by the right hand with the fingers pointingto the direction of the current flow, the outstretched thumb will
point to the north pole
Unit Pole A pole which when placed in air from a similar and equal polerepels it with a force of 1/4pi newtonsMagnetic Pole Point in a magnet where the intensity of the magnetic lines offorce is max
Magnetic Axis Straight Line passing through 2 poles of a magnetDia UrUo ; aluminum, platinum, manganese, chromium,oxygen
Greatest % of materials
Ferro Ur>>1 U>>Uo ; cobalt10^-10 m Diameter of atom10^-15 to 10^-16m
Diameter of atomic nucleus
1.1 x 10^-8 cm Diameter of Hydrogen AtomPermeance Reciprocal of Reluctance / Analogous to conductanceCoercivity Amount of magnetizing force to counter balance the residual
magnetism
Leakage Factor Ratio of flux in iron to flux in air (iba iba yung tawag sa book atsa coaching)
IntensityMagnetism
The flux density produced in it due to its own magnetism
Hysteresis Lag between B and HFerrites Non metallic materials that have ferromagnetic propertiesAir Gap Air space between magnetsKeeper Used to maintain the strength of magnetic fieldMoving electricalcharge
Where all magnetic field originates from
Stationary ElectricalCharges
Magnetic field does not interact with this
Uniform Magnetic field inside a solenoidCurrent CarryingWire Loop
Resembles the magnetic field of a bar magnet
North A current is flowing east along a power line. If the earths fieldis neglected, the direction of the magnet below it is
revolution When a wire loop is rotated in a magnetic field, the direction ofthe induced emf changes every
Domain Group of magnetically aligned atoms
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Toroid Electromagnet with its core is in the form of a close magneticring
Hall effect Small voltages generated by a conductor with current in anexternal magnetic field
Effect which is generally used in the gaussmeter to measureflux density
Edison effect Emission of e- from hot bodiesWiegand effect Ability of a mechanically stressed ferromagnetic wire to
recognize rapid switching of magnetization when subjected by
a dc magnetic field
Wall Effect Contribution to the ionization in an ionization chamber by e-from the walls
Bridgman effect Phenomenon when current passes through an aristropic crystal,there is an absorption of heat due to the non uniformity in
current distributionHydrogen Simples atom to exist; it is a diamagnetic materialGermanium 32p+, 32e- and 40n = 72Ge32 =
(AtomicWeightGeAtomicnumber)
Atomic Mass Sum of proton and neutrons (di ko sure pero eto nakalagay e)Atomic Number # of protons or # of electrons72.6 Ge exact atomic weight28.09 Si exact atomic weight at 300K# of protons Determines the atomic # of an elementCopper 34nMetallic bonding Atom bonding due to the force of attraction between groups of
+ ion and ion
Motor Action Physical motion resulting from the forces of magnetic fieldFlux linkages = flux x # of turnsElectron Volt (eV) Customary energy unit in atomic and nuclear physicsJoule, Watt-sec,KW-h
Units of electrical energy
KW-h Practical unit for electrical energyIon An atom or group of atoms carrying a net electrical chargeThermionicemission
Evaporation of e- from a heated surface
Amber Greek word for electronPlasma Charged GasesExclusion Principle Principle that states that each e- in an atom must have a
different set of quantum numbers
Pauli ExclusionPrinciple
Principle that states that only 2 e- with differebt spins are
allowed to exist in a given orbit
Radio Freq Common application if an air-cored choke
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Ohms Law For linear circuits (AC,DC)Crystalline Solid One of the solid structures in which the position of the atoms
or ins are predetermined
Amorphous Solid with no defined crystal structure; also called non-crystalline
Permits mechanicalClearance Reason for air gaps between rotor and statorVan der Waals Bond Formed when there exist distant electronic interaction between
opposite charges present in the neighboring atoms or
molecules
Atomic PackingFactor
Measures compactness of crystal = atom volume/cell volume
Madelung Constant Corrects the electrostatic forces of the more distant ions in anionic solid
Creepage Conduction of electricity across the surface of a a dielectricAurora Corona discharge1.15 to 1.25 Leakage coef for electrical machinesAstrionic Science of adapting electronics to aerospace flightAir Has straight BH curve passing through the originSoft iron BH curve not straightUsing material withnarrow hysteresisloop
Reduces hysteresis loss
Silicon steel Least hysteresis loop areaUnlimited # of compounds in natureOhm-m SI unit for specific resistanceSiemens / Mhos SI / CGS for conductanceSiemens/m SI for conductivityResistivity Temperature
For Conductors
2 Wb/m^2 Typical saturation flux density for most magnetic materialsinsulators Temp coefficient of resistance is NEGATIVE;
Temp coefficient of resistance is directly proportional to T;
R is inversely proportional to T
semiconductors Temp coefficient resistance is NEGATIVEconductors Temp coefficient resistance is POSITIVE;
Temp coefficient of resistance is inversely proportional to T;
R is directly proportional to T
Temp coefficientresistance
Dependent on nature and temp of material
Tells how much the R changes for a change in T
+ temp coef Manganin, Tungsten Filament- temp coef Electrolytes, carbon.0034 Temp coef of resistance of pure gold
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.0038 Temp coef of resistance of silver
.0039 Temp coef of resistance of leadAlmost 0 Eurekas Temp coefficient resistanceSilicon Carbibe Ohms law cannot be applied to this material10x Hot R = ___x Cold RNeutral A body under ordinary conditionsDielectric constantorSpecific InductiveCapacity
Another name for relative permitivitty
BreakdownVolatage
Another name fore Dielectric Strength (V/mil)
Magneticconductivity
Another name for permeability
1/(oo) = c2 Relationship of Eo and Uo and c (light velocity)1 and 10 Dielectric constant of most materialsMica Insulating material used in an electric ionPorcelain Insulating material used in voltage transformersEarphones Uses permanent magnetsMotors Uses temporary magnets
CHAPTER2+ to - Conventional Flow- to + Electron FlowW P true powerVAR Q reactive powerVA S apparent powerPower factor Cos = P/SReactive factor Sin = Q/SVoltageMagnification Factor
Q Factor of Series resonant circuit
CurrentMagnification Factor
Q factor of // Resonant Circuit
Voltage Resonance Series ResonanceCurrent Resonance Parallel ResonaceIonization Current Results from free electronsELI Series Resonace / Acceptor CircuitICE Parallel Resonance / Rejector CircuitELI by exactly 90deg
Pure inductance
ICE by exactly 90deg
Pure capacitance
ELI by less than 90deg
RL
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ICE by less than 90deg
RC
Reactance = 0 If I and V are in phase for an AC circuit0.707 Current is ____ times the max current at half power points of a
resonance curve
Gang Capacitor Variable Capacitor which the C is varied by varying the platearea
Trimmer Capacitor A variable capacitor in which C is varied by changing distancebetween plates
55 ohm-cm Specific resistance of pure Ge60 ohm-cm Resistivity of pure Ge under standard conditions55 ohm-cm Specific resistance of pure SiLeading or Lagging Power factor of series RLC at its half power pointsLeading pf Capacitive LoadLagging pf Inductive LoadSeparation of thehalf power points Meaning of BW in series RLCEffective Value Most important value of a sinewaveFaradic current An intermittent and non symmetrical alternating current like
that obtained from the secondary winding of an induction coil
Stray Capacitance Capacitance that exists not through design but because 2conducting surfaces are relatively close to each other
1.73 Peak factor of a triangular waveTriangular Wave Peakiest waveformIndependent toeach other
Reason for // connection of appliances in homes
Appliances havedifferent currentratings
Reason why not in series connection of appliances in homes
Sinusoidal Most popular waveformSquare wave Most common non sinusoidal waveformIdeal CurrentSource (parallel r)
Infinite internal resistance
Zero internal conductance
Ideal VoltageSource(series r)
Zero internal Resistance
Infinite internal conductance
Ideal Ammeter(in series to thecircuit)
R is 0
Ideal Voltmeter(in // to the circuit)
R is infinite
Resonance Curve Frequency VS CurrentReactance Chart Estimates the resonant freq and to find the reactance at any
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freq for any value of C or I
Edge Effect Refers to the outward curving distortion of the lines of forcenear the edges of 2 // metal plates that form a capacitor
The narrower thepassband
(For Series RLC), the higher the Q
Internal Heating Leakage resistance in a capacitor results toPhase The_____ of an alternating quantity is defined as the fractionalpart of a period or cycle through w/c the quantity has advanced
from a selected origin
3.7K Metal tin becomes a superconductor at this tempIt has a varyingmagnetic field
Reason why AC can induce voltage
Exponential Law Charging of capacitor through a resistance obeys _______Sinewaves The factor 0.707 for converting peak to rms applies only to
_____
Joule Term to express the amount of electrical energy stored in aelectrostatic field
Breakdown Voltage Refers to the lowest voltage across any insulator that cancause current flow
Blocks DC current Capacitor47 ohms Preferred value of resistor (among the choices which are 520,
43K and 54K)
Electrolyticcapacitor
Most suited for dc filter circuits;
Highest cost per uF;
Only Capacitor used in DC circuits;
Used in Transistor amplifiers
Variable Capacitor Used air dielectricBarium StrontiumTitanite Dielectric
Also called ceramic
Surge Voltage Max voltage that can be applied across a capacitor for a shortperiod of time
Voltage It is used as the reference phasor for // AC circuitsIt has reactance inradio freq circuits
Disadvantage of wirewound resistors
Manganin Most common material for wirewoundTemp coef Indicated by the first band for a 5band method of capacitor
color coding
Rate at whichelectrons pas agiven point
Determines the magnitude of an electric current
Q of 10 Means that the energy stored in the magnetic field of the coil is10x the energy wasted in the resistance
770V Neon lamp ionizes at approx _____
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AnticapacitanceSwitch
Switch designed to have low capacitance between terminals
when open
Bifilar Resistor Resister wound with a wire doubled back on itself to reduceinductance
Alloy Fusion of elements without chemical action between themVpeak Used in calculating max instantaneous powerVrms Used in calculating VaveMaximumcapacitance
Happened when movable plates of gang capacitor overlaps the
fixed plates
Thevenins Theorem Used for analysis of Vacuum tubesPhasor Rotating vector whose projection can represent either current
or voltage
CHAPTER31 # of e- in 4th orbit of copper atom8 e- Each atom in a Si Crystal has _____ in its valence orbit32 p+ Silicon Atom has ____More slowly e- in the largest orbit travel _______ than the e- in smaller
orbits
Intrinsicsemiconductor
Pure Semiconductor
Extrinsicsemiconductor
Doped semiconductor;
2 Ohm-cm = resistivity
2mV/C For Ge or Si diodes, the barrier potential decreases _____Piecewise LinearModel
A diode modeling circuit which considers the threshold voltage,
Rave and switch as the diodes equivalent
Diffusion and drift 2 mechanisms by which holes and electrons move through a Sicrystal
Diffusion Random motion due to thermal agitation in the movement ofh+ and e- in a Si crystal
Drift Current Happens when charges are forced to move the electric field ofa potential difference
Carrier Drift Mechanism for carrier motion in semiconZener and AvalanceEffects
Two possible breakdown mechanism in PN jxn diodes
Zener Breakdown Electric field in the depletion layer increases to the point whereit can break covalent bonds and generate electron-hole pairs
AvalancheBreakdown
(In semiconductors) this takes place when the reverse bias
exceeds a certain value;
Happens when the minority carriers that cross the depletion
region under the influence of the electric field gain sufficient KE
to be able to break covalent bonds in atoms
Avalance effect Occurs are higher reverse voltagesDiffusion or Storage Is the forward bias capacitance of a diode
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CapacitanceLifetime Amount of time between the creation and disappearance of a
free electron
Recombination Annihilation of e- and h+;Merging of e- and h+
Transit time Time taken by e- or h+ to pass from emitter to collectorReverse recoverytime
Time taken by a diode to operate in the reverse to forward
condition;
Time it takes to turn off a FB diode;
= storage time + transition interval from F to R bias
Insulator At room temp, silicon acts like a ______Compound Semicon Gallium Arsenide, Alluminum Arsenide and Gallium Phosphide
are classified as ______-
Increase electricconductivity
Purpose of adding impurities
Ptype semicon Silicon doped with trivalent impurity;Holes are majority carriers
Ntype semicon Silicon doped with pentavalent impurity;Electrons are majority carriers
Trivalent Atom Acceptor Atom;Boron, Indium, Gallium,
Pentavalent Atom Donor Atom;Phosphorus, Arsenic, Antimony, Bimsuth
N type Forms when the # of free e- in a doped semiconductor isincreased;
Forms when pentavalent atom is added
P Type Forms when the # of free e- in a doped semiconductor isreduced
Forms when trivalent atom is added
PN crystal Other name for Jxn Diode;Commonly rated by its PIV and max forward current;
Max forward current is limited by Jxn Temperature
Dipole Each pair of + and ions at the jxn is called _____Barrier Potential Inversely proportional to tempHigh field emission Creation of free electrons through a zener effectIntensity of electricfield
Zener effect depends on this
Forward current Most impt diode parameter which gives the current value adiode can handle without burning
Reverse BreakdownVoltage
Maximum reverse voltage that can be applied before current
surges
Esaki Diode Tunnel Diode;Principal char is that it has negative resistance region;
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Widely used in oscillators, switching networks and pulse
generators
Schotty Diode Most impt application is digital computersShocklet Diode No depletion layerBulk resistance Sum of the P and N regions resistances;
rB = (V-VT)/IVAristors Are transient suppressorsVaractor Diode Also known as epicap, varicap, voltage-variable capacitance,
voltacaps;
Used for tuning the Receivers and is normally operated at
reverse biased
Point Contact diode Used metal cat whiskers as its anode;Classified as hot carrier diode
PIN diode Used in RF switches, attenuators and other phase switchingdevices
Bulk resistancedecreases insemiconductors
If doping increases, ___________
High Resistance Lightly doped semiconductors have ____Less than 1 ohm Typical bulk resistance of rectifier diodesTransition regioncapacitance
The reverse bias diode capacitance is termed as ______
LED Equivalent to a optocoupler ;Typical operating current is 10mA;
Voltage drop is 1.5V;
Constructed using Gallium Arsenide;
Gives light when FB
LAD A photodiode which conducts current only when FB and isexposed to light;
Also called photodiode
IR emitters Solid state GaAs devices that emit a beam of radiant flux whenFB
Optocoupler Also known as optoisolatorSecondapproximation
(for diodes) an equivalent ckt of a diode in which it is
represented as a switch series with barrier potential
Third approximation (for diodes) an equivalent ckt of a diode in which it isrepresented as a switch in series with a resitanceNegative voltage
suppliesNeeded for PMP voltage divider bias
16.7 ms Halfwave signal (1/60Hz)8.33 ms Fullwave signal (1/120Hz)40.6% Max rectification efficiency of HW81.2 Max rectification efficiency of FW
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MOSFET Highest Zin;Sometimes called Insulated Gate FET
FET Has least noise level;Has higher Zin compared to BJT due to its input which is
reverse biased
uA Typical leakage current in a PN jxnOhms Resistance of a FB PN jxnDerating Factor Shown on a data sheet that tells how much you have to reduce
the power of a device
Dember Effect Or Photodiffusion effect;The creation of voltage in a conductor or semicon by
illumination of one surface
Bulk Effect Effect that occurs within the entire bilk of a semiconductormaterial rather than a localized jxn
Skin Effect Increases the resistance of wires at high frequenciesAnotron Diode A cold cathode glow-discharge diode having a copper anode
and a large cathode of sodium or other material
BARITT Diode A microwave diode in which the carriers that transverse thedrift region are generated by minority carrier injection from a
FB jxn instead of being extracted from the plasma of avalanche
Spacistor Multiple terminal solid state device similar to transistor thatgenerates frequencies up to avout 10,000 Mhz by injecting e-
or h+ into a space charge layer
Zener Diode Principal char is that its voltage is constant under conditions ofvarying current;
Used as a voltage regulator or reference voltage
Voltage multiplier Converts AC to DC, where the DC output can be greater thanthe AC input
PhotoconductiveCell
Or Photoresitive device
Emitter Resistor Most commonly used for biasing a bipolar jxn transistorSilicon Not a good conductor;
Has the smallest leakage current
% Ripple = (Vac / Vdc) x 100Ripple Voltage = (rZ / (rZ+rS)) x VHoles As a general rule, _____ are found only on semiconductors;
An incomplete part of an electron pair bond;
Vacancy left by free electrons
Isotopes A nuclei with common # of p+ but different # of neutronsSeries Capacitors In power supplies, circuits that are employed in separating AC
and DC components and bypass AC components around the
load are called _______
Emitter Follower Av is low and usually less than 1;
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Circuit Ai is High;input is in-phase with output;
Employs 100% negative feedback;
Used for impedance matching;
Equivalent to CC amplifier
BJT / transistors Current controlled device;Largest region is the Collector Region
FET Voltage controlled device;Has 5v pinch off voltage;
FET transcoductance = IC/VGS ;
Square Law Devices;
At cut-off, the depletion layers are touching
Transistors Converts DC power to AC powerPower Transistors Made in large sized to disspate more heatPower amplifiers Input is DCOscillators Converts DC power to AC powerOhmic Equivalent if transistor at saturation in JFET is ______IGFET Another name for MOSFETCMOS Easily damaged by static chargesSaturation region Used by FET (EMOSFET) to act as an amplifierTriode region andSaturation Region
Used by FET (EMOSFET) to act as a switch
10uF Coupling capacitor value in RC coupling;Coupling capacitor (Cc) must be high enough to prevent
attenuation of low freq
Qpoint /OperatingPoint
Point of intersection between a diode characteristic and a load
line;
Intersection of dc and ac load lines
Luminous Efficacy Measure of the ability of any LED to produce lumens perapplied watt of energy
Scale Current Another name is Saturation CurrentInput Char Curve A graphical representation in a transistor where the IE is
plotted against the variable VEB for constant VCB
Output Char Curve A graphical representation in a transistor where the Ic is plottedagainst the variable VCB for constant IE
RC coupling Used in low level, low noise audio amplifiers to minimize humpick up from stray magnetic fieldsTransformer
CouplingMajor advantage is permitting power to be transformed from
the relatively high output impedance of the first stage to the
relatively low input impedance of second stage
1.12eV(Si) and0.72eV(Ge)
From these conditions, it can be said that less # of electron-
hole pair will be generated in Si than in Ge
0.135 m2/V-s Electron mobility in silicon
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Harold Black Invented feedback amplifier in 1928Always points to Nand away from P
Arrows in semiconductor symbols
CE circuit Conventional amplifierJunction and PointContact
Structural category of a semiconductor diodes
Threshold Voltage Turns on an enhancement-deviceDMOSFET Acts mostly as a FET;
Can operate in D and E
EMOSFET Can only operate in EHeat dissipation Most important factor of a power transistorCollector Efficiency Most important consideration in power amplifiersDrift transistor Has a high frequency cut off due to its low inherent internal
capacitance and low electron transit time
Poor frequencyresponse
Results when transistors are used as video amplifiers
Fission Break up of nuclei into nuclear fragments that are nucleithemselves
Neutrino Zero charge and zero massEG => 5eV Energy gap for insulatorsEG = 1.1eV Energy gap for Si semiconductorsEG => 0.67eV Energy gap for Ge semiconductorsBound Electrons Tightly holds the 8 e-25mV Thermal Voltage at room temp;
Thermal voltage causes holes in intrinsic semiconsuctors
8.62 x 10^-5 eV/K Boltzman constantVoltage divider Bias Preferred form of biasing a FETVGS(OFF) = VGS(ON) For N-channel EMOSFETBeta CE gain
= IC/IB
Alpha CB gain= IC/IE CHAPTER4
Collector has reversebias
Reason why a transistor amplifier has high output impedance
Gain-BW product Considered as an amplifier figure of meritLogic probe In an oscilloscope, it is used to indicate pulse condition indigital logic circuit
Logic analyzer Used to sample and display systems signalOscillators Produces undamped oscillationsBiasing Establishes a fixed level of current or voltage in a transistorAF transformer It is shielded to prevent induction due to stray magnetic
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fields
Amplitude Distortion Or harmonic distortionFrequency Ear is not sensitive to thisRC coupling To separate bias of 1 stage to another stage;
Used for voltage amplification;
Av is constant over mid frequencies;Most economic type of coupling;
Not used to amplify extremely low freq because electrical size
of the coupling capacitor becomes very large;
Type of coupling used in the initial stage of a multistage
amplifier;
Transformer coupling Used in power amplifiers;Provides high freq because DC resistance is low;
Used when load resistance is very low;
Type of coupling used in the final stage of an amplifier;
Introduces frequency distortion;
Most expensive type of coupling;
Provides high gain because it employs impedance matching;
Can be used either in Voltage or Power amplifiers
DC coupling Best freq response;Used to amplify dc signals in multistage amplifier;
Achieves minimum interference in freq response
Klystron Oscillator Used in order to produce freq in the microwave regionStep DownTransformer
Used for impedance matching;
It is also used as the output transformer in power amplifiers
Gives distortedoutput
Disadvantage of impedance matching
Campbell and Wagner Where the basic concept of electric wave filter originated10Khz Freq that produces highest noise factorCoupling Capacitor The input capacitor in an amplifierBigger AC load line slope is ____ then DC load line slopeAt least 2 transistors Used by multistage amplifierGenerator Outputlevel is kept constant
To obtain the frequency response curve of an amplifier
Relaxation oscillator Type of oscillator where the frequency is determined by thecharge and discharge of RC networks used in conjunction
with amplifiers or similar devicesGPS Instrument used to measure ones location in terms ofcoordinates
1/( 4(LC) ) Cutoff freq for constant-k high pass filterThe smaller the %VR The better!Thin base Transistor should have a _____ to have more AvDarlington Pair Its advantage is that it increases overall Beta Gain
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Independent A feedback network is _______ of frequencyFeedback Networks They employ resistive networksPositive Feedback Employed by Oscillators;Negative Feedback Employed by amplifiers
Reduces distortion;
Reduces gain;Increases BW of an amplifier;
The sacrifice factor is (1+A)
Feedback factor () Is always less than 1;= (1/Af) (1/A)
= Vf / V
Approx gain of anamplifier withnegative feedback(Af)
Reciprocal of feedback factor;
= 1/
(A) in negativefeedback Very much greater than 1 to obtain good gain stabilityPower Again (Ap) = Av x Ai;
Main consideration in the output stage of an amplifier
Crossover network A pair of filter common on a high fidelity system whichseparates audio freq band signals into 2 separate groups
where one is fed to the tweeter and the other to the woofer
Armstrong circuit Simplest variable freq sinusoidal oscillator10uF Typical value of Coupling capacitor50uF Typical value of emitter bypass capacitor in a CE multistage
amplifier
Re, reand Input R of CE amplifier is affected by ________Out of phase (180deg)
Output is always _______ with the input signal in a CE
amplifier
Zero Phase difference between collector voltage and signal voltagein CE amplifier
Increase Av Purpose of emitter bypass capacitor in CE amplifier is to_____
LC oscillator Used only in/for high freqRC Oscillator Used only in/for low freqSine wave oscillator Composed of 1 or more amplifying devices with some freq
determining networks introducing + feedbackHartley Oscillator Used commonly in Radio RxCrystal Oscillator Used commonly in Radio Tx;
Fixed frequency oscillator;
Has fewer loses and will generate alternating emf longer than
LC circuit when shock excited
Tuned Amplifier Operated in Class C;
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Used in Radio freq
Wien Bridge Oscillator Frequency stability of the oscillator output is maximum________;
Employs both + and feedback;
Used in signal generators in laboratories;
Hum in the circuit A pulsating DC applied to the power amplifier causes ______Low Output Important limitation of Crystal OscillatorHigh Q Reason why crystal oscillator freq is very stableMore than 10,000 Typical Q of a crystalPush Pull amplifer Commonly employed at the output stage of an amplifierX axis Cutting perpendicular to end to end;
Electrical axis;
Connects the corners of the crystal
Y axis Cutting perpendicular to face to face;Mechanical
+ temp coef When crystal freq increases with temp- temp coef When crystal freq decreases with tempZero temp coef When crystal freq doesnt change with tempMore batteryconsumption
Low efficiency of a power amplifier results in ______
Buffer Amplifier Used for minimum loading and minimum mismatchHand capacitance If you move towards an oscillating circuit, its freq changes
because of the ______
Ic becomes maximum When transistor is at saturationMaximum voltageappears acrosstransistor
When transistor is at cut-off
At minimum In an LC circuit, when the Capacitor energy is at max, theinductor energy is _____
AC load line The operating point in a transistor amplifier moves along______ when AC signal is applied
Power stage Also called output stage in an amplifierDC At zero signal conditions, a transistor sees _____ loadSum of AC and DC The current in any branch of a transistor amplifier that is
operating is the _____
CMRR = infinity For an ideal differential amplifierTo set up anoperating point
The purpose of dc conditions in a transistor is _____
To avoid drop in gain The purpose of an emitter capacitor is _____Collector Supply The Poutput of a transistor amplifier is more than the P input due
to the additional power supplied by _______
Low When a transistor feeds a load of low R, its Av is _____25% Max collector efficiency of Resistance Loaded Class A power
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amp
50% Max collector efficiency of Transformer coupled Class A poweramp
RF amplifiers Class C amplifiers are used asDriver stage Employs class A amplifiers1NPN, 1PNPtransistor
Complementary-symmetry amplifier
Increases InputImpedance,Decreases OutputImpedance
Negative voltage feedback
Decreases InputImpedance,Increases OutputImpedance
Negative Current Feedback
ID The Quiescent current of a FET amplifier is _____AND gate The frequency response of the combined amplifier can be
compared with an ______
CHAPTER 6DArsnoval Best type of meter movementWattmeter A dynamometer type which has uniform scale;Dynamometer Most expensive;
Mainly used as wattmeter;
Can be used for AC or DC worksPermanent MagnetMoving CoilInstruments
Can only be applied to DC work only;
The reason why its scale is uniform is because it is spring
controlled;
Springs provide the controlling force;
Most sensitive instrument
Moving Ironinstruments
Considered as attraction and repulsion instruments;
Typical IFS is 50mA;
Typical VFS is 50mV;
Uses squared scale;
Induction watt-hrmeter
Most commonly used induction type of instrument
Watt-hour meter Is an integrating type of instrumenrRest When both deflecting and controlling torque act, the pointer
of an indicating instrument comes to ______
Deflecting force (for analog ins) Causes the moving system to deflect from itszero position
Controlling force (for analog ins) Ensures that the deflection of the pointer for
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a given value of measured quantity always has the same
value
Damping force (for analog ins) Quickly brings the moving system to rest inits final position
Damping andControlling Torques
Opposes the deflecting torque
Damping torque iszero
If the pointer is in the final deflected position
Thermocouple Instrument where output voltage is proportional to thetemperature;
An ammeter used to measure high freq currents
Thermistor Type of resistor used to measure temp changes with changein resistance
Never When should a fuse be replaced by a higher rated unit?Pulse width Time interval that a waveform is High or low is _____ of the
signalPulse delay Time delay between pulsesPeriod The interval of a pulse from start to endCRT Heart of CRO (cathode ray oscilloscope)Wheatstone Bridge Measures resistance accurately;
Balanced if there is no current the flows through the load;
R1/R2 = R3/R4
Potentiometer Bridge Measures Voltage accuratelyMaxwell Bridge Measures unknown inductance with in terms of known
capacitance;
Used to measure medium coils (1
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measurements.
Grid-dip meter Measures tank circuit frequencyMilliamter Operates in the magnetic attraction-repulsion principlesMultimeter Provides RMS measurements for sinusoidsKelvin electrostaticmeter
Fluid friction damping is applied to _______
Negligible The temp coef of resistance of a shunt material is _____Manganin Shunts are generally made of ____Aluminum Pointers are generally made of ____Zero adjust Used to balance both halves of the difference in amplifier or
cathode coupled amplifier in VTVM
DMM Type of meter that provides precise reading of V,I,R wherethere is generation of samples at the input and feeds it to a
digital read-out
Sensitivity The smallest signal that can be reliably measured in VTVTMRSH = (IFS x Rm)/(IT IFS) Rm = internal resistanceLissajous Pattern Pattern displayed by the oscilloscope which has steady state
char
At half of full Indicating instruments are assumed to be most accurate at_____ part of the scale.
At far right 0 mark is located ______ for a simple ohmmeterResolution The smallest change in applied stimulus that will indicate a
detectable change in deflection in an indicating instrument
CHAPTER 7Inductor Cannot be fabricated in ICTo produce change inoutput when an inputvoltage equals areference voltage
Purpose of comparator in OP-AMP
OP-AMP Mostly uses positive feedback;High Zin, Low Zout, BW is infinity, open loop gain is infinity;
Most commonly used type of linear IC;
50mW typical power dissipated of OP-AMP;
500mW absolute max rating for OP-AMP interval power
dissipation
1V/us typical slew rate of OP-AMP
30V absolute max rating for an OP-AMP differential input
voltage
20dB/decade rate of gain reduction in OP-AMP
80nA typical input bias current of 741 OP-AMP
25mA short circuit current output of 741 OP-AMP
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0.5V/uS slew rate of 741 OP-AMP
2 - # of power supplies required by 741 OP-AMP
OP-AMP magnitudecomparator circuit
Doesnt use feedback
OP-AMP input biascurrent Is the average of the 2 base currentsuA741C OP-AMP Is used for commercial purposes;
Its CMRR = 70dB
Voltage follower An OP-AMP circuit that has its output tied directly to theinverting terminal
Summing Point in anOP-AMP
A terminal of the OP-AMP where the input resistors are
commonly connected
Ratio of Rf/R must beequal to thereciprocal of thenumber of inputs
Condition to convert a summing amplifier to an averaging
amplifier
Negative The summing amplifier has 2 or more input and its outputvoltage is proportional to the _______ of the algebraic sum
of its input voltages.
Power BW The highest undistorted freq output of an OP-AMP for a givenslew rate and peak voltage
Less than 1W Power dissipation of most low power linear IC2 mega ohms Typical input resistance of the OP-AMP when measured under
open loop
555 timer Most popular IC in used in timing circuits;Can be used in monostable and astable applications
Square wave clock _____ is an astable multivibrator (relaxation oscillator)RC synthesis Technique used to eliminate the need for inductive elements
in monolithic IC
Single-Stone Monos / LithosSSI Up to 9 gatesMSI 10 to 100 gatesLSI More than 100 gatesVLSI More than 1000 gatesBIFET IC OP-AMP that combines FETS and Bipolar transistorsRelaxation oscillator Operates on the principle of the charge and discharging of a
capacitor
Digital IC Possesses digital signalsLinear IC Possesses analog signalsThick Film and ThinFilm
We can use ____ and _____ if higher power ICs are needed.
Common Mode signal Signal that is applied with equal strength to both inputs of a
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differential amplifier or an OP-AMP
-55 to +125 degCelsius
Military and space IC
-25 to +85 degCelsius
Industrial IC
0 to +70 deg Celsius Commercial ICMilitary and Industrial After assembly, the ICs are tested and classified as either______.
DIP packaging Low in cost;Tiniest packaging known;
Ruggedly resists vibration
ICs advantages overdiscrete devices(soldered devices)
Lower cost;
High reliability;
Smaller in size
VCO It exhibits a freq that can be varied with a DC control voltageAv = Rc / 2Re Voltage gain of a differential amplifierThe difference in VBEvalues
Source of output offset voltage
manufacturer Letter-prefix code indicates the ______Packaging type Letter-suffix code indicates the _________D, J, N Most common packaging typeD packaging suffix for Plastic DIP for surface mounting on a PC
board
P,N packaging suffix for Plastic DIP for insertion in socketsJ packaging suffix for Ceramic DIP1.5 mils x 3 mils Typical dimension of a MOSFET in a single chip IC3 mils x 4.5 mils Typical dimension of a DIODE in a single chip IC4 mils x 6.5 mils Typical dimension of a BJT in a single chip ICIt has an inherentcurrent limiting
Advantage of a shunt regular type over a series regulator
type
Flat response Type of response that characterizes a single pole low passfilter
Single RC circuit The term pole refers to a ________ in terms of circuitcomponent.
Stray wiringcapacitance
Unwanted capacitance between connecting wires and ground
1M transistors Intel i486 32 bit microprocessor has _________ on a singlechip
Trip point It is the value of the input voltage that switches the outputcomparator or Schmitt trigger
Virtual ground Type of ground that appears at the inverting input of an OP-AMP that used negative feedback
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CCD (charge-coupledCapacitor)
1969; by WS Boyle and GE Smith
0.5 to 15GHz Microwave ICs cover the freq rangeThe inverting input isconnected to the +5V
In a 5V level detector circuit, ______________
Ground To use a comparator for zero-level detection, the invertinginput is connected to the ___
Czochralsky Pullingtechnique
Most common method used for the growth of single crystals
for IC farbrication
CompensatingCapacitor
Prevents oscillations inside an OP-AMP