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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
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