Terms - Prelims Flashcards
a reverse-biased diode acts like a(n)
open switch
the arrow in the schematic symbol for a diode point which way?
in the direction of current flow
the forward bias a diode
an external voltage is applied positive at the anode (p-region) and negative at the cathode (n-region)
the cathode of a semiconductor diode indicates a _______ charge during conduction
negative
an electronic device that allows an electric current to flow in one direction
diode
electron collector
anode
an electronic switch allows or prevents the flow of the current in a circuit
diode
what does a high resistance reading in both foward and reverse-bias directions indicate?
open diode
in a semiconductor diode, the depletion region is removed when
the diode is in its forward conducting state
type of diode that is made of metal whisker touching a very small conductor die
point contact diode
refers to the majority carrier in an N-type semiconductor
electron
how many does an ohmmeter behave if its positive lead is connected to the cathode of a diode while negative to anode?
has infinite high resistance
as you increase the doping level of a crystal diode, its voltages
increases
how many diodes will you use in designing a half-wave rectifier power supply?
one
how does zener diodes widely used?
voltage regulators
when the diode is in its non-conducting state, it has
a very high resistance
the process of converting AC input to AC output to DC output
rectification
the output of a half-wave rectifier
half-wave rectified signal
a half-wave rectifier circuit utilizing one half of an ac input cycle hacve a ripple frequency in its output equivalent to
60 cps
an amplifier with an input resistance of 600 ohms has an input current of 500 uA. It delivers 100 mA to a 1000-ohm load. Calculate the dB gain of the amplifier
48.2 dB
Reducing the plate and screen-grid voltage of an amplifier will ______ control grid cut-off voltage
increase
the zone in a semiconductor diode where no free charge carriers exist is known as
depletion region
the process in which the DC level is obtained frm sinusoidal input can be improved 100%
Full-wave rectification
the valence electron of a conductor is also called as
free electron
valence electrons are
in the most distant orbit from the nucleus
an atom consists of
one electron, proton and neutron (both inside one nucleus)
part/s of an atom that causes current
electrons
semiconductors that have been carefully refined to reduce the impurities to a very low level as pure as can be made available through modern technology
Intrinsic Materials
semiconductors that are subjected through a process known as “doping”
Extrinsic Materials
process of adding of impurities to a pure semiconductor material to change their electrical properties
Doping
Elements that are dopant, p-type doping
Boron and gallium
Acceptor impurity creates
a hole
Examples of Donor, N-types
Phosphorus and Arsenic
Examples of Donor, N-types
Phosphorus and Arsenic
Donor impurity contributes
free electrons
p-type material formed by doping an
trivalent impurities
n-type material formed by doping
pentavalent impurities
in p-type materials, holes are
major carrier
in n-type materials, electrons are
major carriers
donor-doped semiconductor becomes a
N-type semiconductor
if you wanted to produce a p-type semiconductor, what would you use?
acceptor atoms
the purpose of pentavalent impurity is to
increase the number of electrons
majority carriers in an n-type semiconductor are
conduction electrons
