Analog Electronics
114 articles • Complete guide
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Curriculum
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Semiconductor Physics
PN junction, energy bands, carrier concentration, drift and diffusion
Energy Band Theory
Valence band, conduction band, forbidden energy gap and band diagrams.
Intrinsic Semiconductors
Pure Si and Ge, intrinsic carrier concentration ni, temperature dependence.
Extrinsic Semiconductors N-Type
Donor impurities, majority electrons, Fermi level near conduction band.
Extrinsic Semiconductors P-Type
Acceptor impurities, majority holes, Fermi level near valence band.
Carrier Concentration
Mass action law np=ni², doping concentration effects.
Drift Current
Drift velocity, mobility, ohmic behavior in semiconductors.
Diffusion Current
Concentration gradient driven current, diffusion coefficient.
Einstein Relation
Relationship between diffusion coefficient and mobility D/μ = kT/q.
Hall Effect
Hall voltage, carrier type identification, Hall coefficient measurement.
Continuity Equation
Carrier generation, recombination, and transport equation.
Diodes & Applications
PN diode, Zener, LED, photodiode, rectifiers, clippers, clampers
PN Junction Formation
Depletion region, built-in potential, contact potential.
PN Junction Forward Bias
Barrier reduction, diffusion current increase, exponential IV.
PN Junction Reverse Bias
Barrier widening, reverse saturation current, depletion width.
Diode IV Characteristics
Forward bias, reverse bias, cut-in voltage, breakdown.
Shockley Diode Equation
Ideal diode equation I = Is(e^(V/nVT) - 1), ideality factor.
Diode Equivalent Circuits
Ideal, piecewise linear, constant voltage drop models.
Diode AC Resistance
Small signal resistance rd, dynamic resistance calculation.
Zener Diode
Zener breakdown mechanism, voltage regulation, line and load regulation.
Zener Voltage Regulator
Regulation circuit design, minimum and maximum load current.
Half Wave Rectifier
Circuit operation, PIV, ripple factor, efficiency, TUF.
Full Wave Center Tap Rectifier
Two diode circuit, PIV, improved ripple factor.
Bridge Rectifier
Four diode bridge, PIV, comparison with center tap.
Capacitor Filter
Filter capacitor, ripple voltage calculation, load regulation.
Pi Filter
LC and RC pi section filters, improved smoothing.
Series Clipper
Positive and negative series clippers, transfer characteristics.
Shunt Clipper
Positive and negative shunt clippers, biased clippers.
Positive Clamper
DC level shifting upward, clamping circuit analysis.
Negative Clamper
DC level shifting downward, biased clamper circuits.
Voltage Multiplier
Voltage doubler, tripler circuits using diodes and capacitors.
LED
Light emitting diode, forward voltage, wavelength, applications.
Photodiode
Reverse biased operation, responsivity, dark current.
Varactor Diode
Voltage variable capacitance, tuning circuit applications.
Tunnel Diode
Negative resistance region, Esaki diode, high frequency use.
Schottky Diode
Metal-semiconductor junction, fast switching, low forward drop.
BJT Amplifiers
BJT characteristics, biasing, CE/CB/CC configurations, small signal analysis
BJT Structure and Construction
NPN and PNP layers, emitter-base-collector doping profiles.
BJT NPN Operation
Forward active NPN, electron injection, base recombination.
BJT PNP Operation
Forward active PNP, hole injection, complementary to NPN.
BJT Current Relationships
Alpha, beta, relationship between IC IB IE, current gain.
BJT Operating Regions
Active, cutoff, saturation, inverse active identification.
BJT Input Output Characteristics
IC vs VCE, IB vs VBE curves, Early effect.
Fixed Bias Circuit
Single resistor biasing, Q-point calculation, stability analysis.
Collector Feedback Bias
Negative feedback biasing, improved stability over fixed bias.
Voltage Divider Bias
Most stable bias circuit, design procedure, Q-point.
Emitter Bias
Emitter resistor stabilization, design methodology.
BJT Bias Stability
Stability factors S(ICO) S(VBE) S(beta), thermal runaway.
Common Emitter Amplifier
CE voltage gain, input and output impedance, phase inversion.
Common Base Amplifier
CB current gain, high frequency advantage, low input impedance.
Common Collector Amplifier
Emitter follower, voltage gain approximately 1, impedance transformation.
BJT Small Signal Model
Hybrid pi model, transconductance gm, input resistance rpi.
H Parameter Analysis
h parameters hie hre hfe hoe, two port BJT model.
BJT Frequency Response
Miller effect, bandwidth, upper and lower cutoff frequencies.
Multistage Amplifiers
Cascaded CE stages, overall gain, loading effect.
Darlington Pair
Super beta configuration, high current gain, input impedance.
Cascode Amplifier
CE-CB cascade, improved bandwidth, Miller effect reduction.
Differential Amplifier
Difference and common mode gain, CMRR, tail current source.
Power Amplifiers Class A
Class A operation, efficiency 25%, transformer coupled.
Power Amplifiers Class B
Push pull operation, crossover distortion, efficiency 78.5%.
Power Amplifiers Class AB
Reduced crossover distortion, biasing for Class AB.
FET Amplifiers
JFET, MOSFET characteristics, CS/CG/CD configurations, biasing
JFET Construction
N-channel and P-channel JFET, gate channel structure.
JFET Characteristics
Pinch-off voltage, IDSS, transfer characteristics, drain curves.
JFET Self Bias
Self bias circuit, graphical analysis, Q-point determination.
Enhancement MOSFET
NMOS and PMOS enhancement mode, threshold voltage, channel formation.
Depletion MOSFET
Depletion mode operation, can operate with zero gate voltage.
MOSFET IV Characteristics
Triode and saturation regions, ID equations, channel length modulation.
MOSFET Biasing Techniques
Voltage divider bias, drain feedback bias for MOSFETs.
Common Source Amplifier
CS voltage gain, high input impedance, design examples.
Common Gate Amplifier
CG low input impedance, no Miller effect, cascode use.
Common Drain Amplifier
Source follower, unity voltage gain, high input impedance.
MOSFET as Switch
Cutoff and triode regions, digital switching applications.
CMOS Inverter Basics
Complementary MOS, voltage transfer characteristic, noise margins.
Operational Amplifiers
Op-amp characteristics, inverting/non-inverting, summing, differentiator, integrator
Ideal Op-Amp
Infinite gain, infinite input impedance, zero output impedance.
Op-Amp Practical Parameters
Open loop gain, CMRR, slew rate, GBW product, offset voltage.
Inverting Amplifier
Gain = -Rf/Ri, virtual ground, input impedance = Ri.
Non-Inverting Amplifier
Gain = 1 + Rf/Ri, high input impedance.
Voltage Follower
Unity gain buffer, impedance matching applications.
Summing Amplifier
Weighted summer, audio mixer, DAC application.
Difference Amplifier
Differential input, CMRR improvement, bridge amplifier.
Instrumentation Amplifier
Three op-amp design, high CMRR, adjustable gain.
Op-Amp Integrator
Integrator circuit, frequency response, practical integrator.
Op-Amp Differentiator
Differentiator circuit, noise sensitivity, practical design.
Comparator
Zero crossing detector, voltage level comparison.
Schmitt Trigger
Hysteresis, upper and lower threshold, noise immunity.
Log and Antilog Amplifier
Logarithmic compression, exponential expansion circuits.
Precision Rectifier
Super diode, half wave and full wave precision rectifiers.
Voltage to Current Converter
Grounded and floating load V-to-I converters.
Current to Voltage Converter
Transimpedance amplifier, photodiode interface.
Sample and Hold Circuit
Acquisition time, hold time, droop rate.
Active Rectifier
Precision half wave and full wave rectifier circuits.
Oscillators & Timers
RC, LC, crystal oscillators, 555 timer, waveform generators
Barkhausen Criterion
Loop gain = 1, phase shift = 0 or 360 degrees condition.
RC Phase Shift Oscillator
Three RC sections, 180 degree phase shift, frequency formula.
Wien Bridge Oscillator
Bridge balance, AGC, frequency = 1/(2piRC).
Colpitts Oscillator
Capacitive voltage divider feedback, LC tank circuit.
Hartley Oscillator
Inductive voltage divider feedback, tapped inductor.
Clapp Oscillator
Modified Colpitts, improved frequency stability.
Crystal Oscillator
Piezoelectric quartz, high Q factor, frequency stability.
555 Timer Astable Mode
Free running oscillator, frequency and duty cycle formulas.
555 Timer Monostable Mode
One shot pulse generator, pulse width = 1.1RC.
Waveform Generators
Square wave, triangle wave, sawtooth generation circuits.
Voltage Controlled Oscillator
VCO operation, frequency proportional to input voltage.
Phase Locked Loop
PLL block diagram, lock range, capture range, applications.
Filters
Active filters, Butterworth, Chebyshev, band-pass, band-stop
Passive RC Low Pass Filter
First order LPF, cutoff frequency fc = 1/(2piRC), roll-off.
Passive RC High Pass Filter
First order HPF, frequency response, phase shift.
Active Low Pass Filter
Sallen-Key topology, gain, second order response.
Active High Pass Filter
Active HPF design, Butterworth response.
Active Band Pass Filter
Center frequency, bandwidth, Q factor.
Active Band Stop Filter
Notch filter, twin-T design, rejection bandwidth.
Butterworth Filter Design
Maximally flat magnitude, pole locations, order selection.
Chebyshev Filter Design
Equiripple passband, sharper roll-off than Butterworth.
Bessel Filter
Maximally flat group delay, linear phase response.
Filter Frequency Response
Magnitude and phase plots, 3dB point, roll-off rate.
Power Electronics Basics
Rectifiers, regulators, SMPS fundamentals
Linear Voltage Regulator
Series pass transistor, regulation, dropout voltage.
78xx 79xx Series
Fixed voltage regulators, pinout, applications.
Adjustable Voltage Regulator LM317
Adjustable output, design formula Vout = 1.25(1+R2/R1).
Switching Regulator Basics
Buck boost topology overview, efficiency comparison with linear.
Other Topics
Latest circuits, troubleshooting, design tips
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