1 Flashcards
What type of crystal lattice is found in silicon and germanium?
face centered cubic (fcc)
What is the energy gap between the valence band and conduction band of a semiconductor?
one electron volt (1 eV)
What is the typical range of the resistivity of a semiconductor?
10 - 10^4 Ω-cm
What type of chemical bond is significant in metals?
metallic bonding
What do you call a semiconductor that is doped with both donor and acceptor impurities?
compensated semiconductor
What is the current flow in a semiconductor due to the applied electric field called?
drift current
What is the movement of charge carriers in a semiconductor without the application of electric potential called?
diffusion current
For high-speed integrated circuits, which semiconductor material is best to use?
gallium arsenide
How much impurity concentration is needed for silicon to change its electrical property from a poor conductor to a good conductor?
one part per million
Which semiconductor has the highest heat conductivity and is used as a heat sink?
diamond
What is the voltage across the gate-source terminal of a FET that causes drain current ID to equal zero?
pinch-off voltage
What is the insulator used in most MOSFETs?
SiO2
According to Shockley’s equation of a JFET, what is the drain current when VGS equals the pinch-off voltage VP?
zero
What is the amount of voltage needed at the gate-source terminal for an enhancement type MOSFET to form a channel for current flow?
threshold voltage
What is the process of growing a thin oxide film on a planar semiconductor device to protect junctions from contamination called?
passivation
If the base-emitter junction is reverse biased and the base-collector junction is forward biased, what region of operation is the transistor in?
cut-off region
What hybrid parameter is usually neglected in most circuit analysis?
hr and ho
What type of compound is GaAs?
Compound
What is a CMOS integrated circuit susceptible to?
damage by static
How is a semiconductor material made into N type?
By adding a donor impurity
Why do holes flow the opposite way from electrons?
Charge carriers are passed from atom to atom
What three-terminal IC regulator has a variable negative voltage output?
337
How do we protect active devices in switching regulators from large over-currents and over-voltages?
by installing a snubber circuit
In a complex control system, what postulates the necessary compensating networks and cross-coupling networks?
compensating network
What is the simplest converter used in motor phase control?
half-wave converter
What term indicates current gain in a common-collector configuration?
Gamma
What is a T flip-flop primarily used for?
To divide the input frequency by two
How is line regulation determined?
by changes in output voltage and input voltage
How is load regulation determined?
by changes in load current & output voltage
In a differentiator, what is the feedback element?
resistor
What type of feedback do Wien-bridge oscillators use?
positive feedback
What is another name for memory?
primary storage
What are common forms of output units?
Printers and screens
What is the period of an AC wave?
Equal to 1 divided by the frequency
What can magnetic flux always be attributed to?
Motion of charged particles
How can the useful current delivered by a solar panel be increased?
By connecting two or more groups of solar cells in parallel
What is an advantage of a rheostat over a potentiometer?
A rheostat can handle more current
What is the force between two electrically charged objects called?
Electrostatic force
How can the capacitance between the primary and secondary windings of a transformer be minimized?
By placing the windings on opposite sides of a toroidal core
Who invented the battery?
Alessandro Volta
For what is Charles Babbage (1792-1871) remembered?
Computers
Who invented the electric generator?
Michael Faraday
In which decade was the transistor invented?
1940s
Who invented Bakelite?
Leo Hendrik Baekeland
