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ELECTRONICS

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What is the bandgap energy for diamonds?

2.5eV

________ allows simplifying a one-port circuit to a current source in parallel with impedance.

Norton’s Theorem

Charge carriers move in semiconductors via two mechanisms: ________ and ________.

drift and diffusion

The diffusion current density is proportional to the _________ of the carrier concentration

gradient

The ________ is the minimum energy required to dislodge an electron from its covalent bond.

bandgap energy

For proper operation, the ________ is forward-biased and the ________ is reverse-biased.

base-emitter junction, base-collector junction

The ________ of the bipolar transistor consists of an exponential voltage-dependent current source tied between the collector and emitter, and a

diode (accounting for the base current) tied between the base and emitter.

large-signal model

The ________ stage provides a moderate voltage gain, moderate input impedance, and moderate output impedance.

common-emmiter

The ___________ provides a voltage gain less than unity, a high input impedance, and a low output impedance, serving as

a good voltage buffer

emitter follower

MOSFETs operate in the ________ region if the drain voltage is more than one threshold below

the gate voltage

triode

A measure of the small-signal performance of voltage-dependent current sources is the _____________ defined as the change in the output current divided by the change in the

input voltage.

transconductance

The impedance seen looking into the gate of a MOSFET is equal to ________

infinity

The _______________ topology exhibits a nominal gain equal to one plus the ratio of two resistors. The circuit also suffers from a gain error that is inversely proportional to the gain of

the op amp.

Noninverting amplifier

Placing a bipolar device around an op amp provides a _____________function

logarithmic

Op amps suffer from various imperfections, including dc offsets and input bias currents. These effects impact the

performance of various circuits, most notably,____________.

integrators

Stacking a transistor atop another forms a _______ structure, resulting

in a high output impedance.

Cascode

Bipolar differential pairs exhibit a ________ input/output characteristic. The tail current can be mostly steered to one side with a differential input

hyperbolic tangent

As the frequency of operation increases, capacitances exhibit a ______________, reducing

the gain. The gain thus rolls off at high signal.

Lower impedance

To obtain the frequency response, we must derive the ___________ of the circuit.

Transfer function

A capacitance tied between the input and output of an inverting amplifier appears at the input with a factor equal to

one minus the gain of the amplifier. This is called _______________.

Miller effect

The ________of a feedback system can, in principle, be obtained by breaking the

loop, injecting a test signal, and calculating the gain as the signal goes around the loop. It determines many properties of feedback systems, e.g.,

gain, frequency response, and I/O impedances.

Loop gain

To avoid oscillation, the gain crossover frequency must __________the phase

crossover frequency.

Fall below

In low-distortion applications, the output stage may be embedded in a _________ to suppress

the nonlinearity.

Negative feedback loop

A push-pull stage operating at high temperatures may suffer from _____________, whereby the elevated temperatures allow

the output transistors to draw higher currents, which in turn makes them dissipate even more.

Thermal runaway

The ___________ response provides a sharper transition than Butterworth at the cost of some ripple in the passband

and stopbands. It contains n complex poles on an ellipse

chebyshev

A phenomenon that occurs for large reverse voltages across a pn junction where the free electrons are accelerated to

such high speeds that they can dislodge valence electrons.

Avalanche effect

A graph showing the gain or phase performance of an electronic circuit at various

frequencies.

Bode plot

What do you call the ohmic resistance of the semiconductor?

bulk resistance

The metaphor used to describe the action of an SCR when it is used to protect a load against

supply.

crowbar

A value that tells you how much to reduce the power rating for each degree above the

reference temperature given on the data sheet.

Derating factor

A condition where the transistor is operating at the upper end of the load line with a base

current that is one-tenth of the collector current.

hard saturation

The pattern appearing on an oscilloscope when harmonically related signals are applied to the

horizontal and vertical inputs.

Lissajous’ pattern

A connection of two transistors connected with positive feedback to simulate the action of a

thyristor.

latch

It refers to the average amount of time between the creation and recombination of a

free electron and a hole.

lifetime

A filter that blocks a signal with at most one frequency.

Notch filter

A term use to describe the death of amplification.

oscillation

The voltage that provides the border between the ohmic region and the constant current region of a depletion-mode device when the gate to source voltage is zero.

Pinch off voltage

A basic circuit that a designer can modify to get more advanced circuits.

prototype

It is a comparator with hysteresis.

Schmitt trigger

Which of the following special purpose diode doesn’t have depletion layer?

Schottky diode

It is define as a large initial current that flows through the diode of a rectifier.

surge current

It is defined as a four-layer semiconductor device that acts as a latch.

thyristor

It is the value of the input voltage that switches the output of a comparator.

trip point

It is a device that acts like two back-to-back-zener diodes.

varistor

What do you call a thin slice of crystal used as a chassis for integrated components.

wafer

What is the other term for zener effect?

high field emission

It is sometimes called hot-carrier diode.

Schottky diode

A network that employ diodes to remove away a portion of an input signal without distorting the

remaining part of the applied waveform

clipper

The time required for the minority carriers to return to the majority carrier state in the

opposite material.

storage time

What is the typical reverse saturated current of a silicon diode?

10 pA

What is the typical range of reverse breakdown voltage of silicon diode?

50-1kV

How does minority carriers produced?

thermally

It is an extremely small amount of current that exists in a reverse biased diode.

reverse saturation current

What does FPGA stands for?

Field Programmable Gate Array

It states that the complement of a sum of variables is equal to the product of the

complements of the variables.

De Morgan’s Theorems

The invalid state for RS flip flop

S=1; R=1

What do you call the number of unique states through which a counter will sequence?

modulus

Asynchronous counters are known as

Ripple counters

The difference between the two op-amp input currents is called ______.

Input offset current

A circuit whose output voltage is proportional to the area under the curve of the input

voltage.

integrator

A circuit whose output voltage is proportional to the slope of the input voltage.

differentiator

A filter response that exhibits an equiripple amplitude response in the pass band.

Chebyshev response

A filter response that exhibits maximum flatness possible in the pass band.

Butterworth response

A ______ is a dc–dc converter with an unregulated input dc voltage and a regulated

output voltage. The converter circuitry consists of arrangements of inductor,

capacitors, diodes, and transistors. The transistors are switched between the ON

state (saturation) and the OFF state (cutoff) at rates that typically range from 10 kHz to 40

kHz.

switched-mode power supply

The time sequence of inputs, outputs and flip-flop states can be enumerated in a _______. This consists of four sections

labeled the present state, input, output and next state.

stable state

In switching transistors, what do you call the time between the changing state of the input

and the beginning of a response in the output?

delay time

The current gain of a Darlington pair is called ________.

superbeta

In digital design of combinational logic circuits, what do you call the term that

refers to the connection of the output of one device to the input of a similar

device allowing one device to drive the other in order to expand the operational

capability?

cascading

In computers, what do you call a relatively small, high-speed memory that stores the most recently used instructions or

data from the larger but slower main memory?

cache memory

Across which components of a power supply does the average (dc) voltage exist?

Capacitor filter

What is the typical value of quality factor for crystal oscillators?

20,000

What is the range of gm for JFETs?

1000 uS to 5000 uS

What is the purpose of an additional RC filter section in a power supply circuit?

Decrease the ac voltage component

The region to the left of the pinch-off locus is referred to as the _____ region.

ohmic

It is the insulating layer of _____ in the MOSFET construction that accounts for the very desirable

high input impedance of the device.

SiO2

Which type of FET has the lowest input impedance?

JFET

What is the maximum power rating for LEDs?

150 mW

Which capacitance dominates in the reverse-bias region?

Depletion capacitance

Which capacitance dominates in the forward-bias region?

Diffusion capacitance

A high resistance reading in both forward- and reverse-bias directions indicate a _______

diode.

open

Which of the following voltages must have a negative level (value) in any NPN bias circuit?

VBC

The _____ model suffers from being limited to a particular set of operating conditions if it is to

be considered accurate.

hybrid

What is the unit of the parameter ho of a BJT?

siemens