Test 1 Flashcards
A ___ is an electronic component that allows electrons to pass through it in only one direction.
Diode
The two most common semiconductor materials used to make diodes are silicon and ___.
Germanium
___ is the addition of impurities to the crystal structure of a semiconductor to allow electron flow.
Doping
___ - type material is semiconductor material created by doping a region of a crystal with atoms of an element that has more electrons in its outer shell.
N
___ voltage is voltage applied with polarity that allows a diode to act as a conductor.
Forward-bias
When a diode is ___, the polarity of the voltage sources causes the free electrons and holes to move away from the depletion region.
Reverse-bias
___ current is the current range in which a semiconductor can safely operate once it reaches forward breakover voltage.
Forward operating currnet
___ voltage is the maximum reverse-bias voltage that a diode can withstand.
Peak Inverses
___ is the flow of electrons when a diode breaks down and allows electrons to pass freely, which can damage the diode.
Avalanche current
Externally, the polarity of a DMM may be identified by a color-coding system – usually ___ for positive and black for negative.
Red
___ is the act of operating a diode at less than maximum operating current.
Derating
Diode applications include ___.
Rectifiers, Clipping circuits, and Clamping.
A ___ is a device consisting of diodes that convert AC power to DC power by allowing electrons to flow in only one direction.
Rectifier
A ___ is a circuit containing an AC source, a load resistor, and a diode that permits only the positive half-cycles of the AC sine wave to pass creating pulsating DC.
Half-wave Rectifier
A ___ is an electronic circuit that consists of diodes used to control voltage when large voltage changes are expected.
Voltage Limiter
A diode ___ circuit can be used when a reference level other than zero is needed.
Clamping
The overall forward and reverse characteristics of a ___ are similar to that of a standard diode.
Zener Diode
The standard zener breakdown voltage tolerance is +/- ___%.
5, 10, and 20.
Zener diode applications include ___.
Voltage regulators, oscilloscope calibration, clipping and limiting.
Resistor ___ establishes the basic zener test current.
RL
Thermionic diodes are the most widely used diodes because of their small size and weight.
F
Some elements commonly used for creating P-type material are phosphorus, arsenic, bismuth, and antimony.
F
Holes are the missing electrons in a crystal structure.
T
Typical elements used for doping a crystal to create N-type material are boron, gallium, and indium.
F
Diodes have the ability to block electron flow in one direction and pass electrons in the opposite direction.
T
A diode has a relatively high resistance in the forward-bias direction and a low resistance in the reverse-bias direction.
F
A diode characteristic curve indicates the response of a diode when subjected to different forward- and reverse-bias voltages.
T
Once the depletion region is closed, resistance across the diode is very low and current increases rapidly.
T
A replacement diode should have at least the same forward current rating as the original diode.
T
In most cases, diodes are tested with a digital multimeter (DMM).
T
Diode testing includes determining the quantity of P-type and N-type material.
F
A DMM set to measure voltage can be used to determine which end of a diode is the cathode and which end is the anode.
F
The best way to test a diode is to measure the voltage drop across the diode when it is reverse-biased.
F
A DMM in the diode test mode is used to test the voltage drop across a diode.
T
A closed diode does not allow electrons to flow through it in either direction.
F
To ensure that diodes operate properly, they should not be overloaded, even momentarily.
T
The maximum current at which a diode may operate in a normal environment is limited primarily by the temperature rise at the PN junction.
T
By connecting a diode in parrallel, it can bypass potentially damaging currents.
T
DC power must be converted to AC power before it can be used to operate electronic devices.
F
A half-way rectifier can affect AC voltage by rectifying or cutting out the negative output voltage.
T
During the clipping process, the diode should not significantly change the shape of a waveform.
F
The main function of a clamper is to provide a DC reference level for a signal voltage.
T
The operation of a zener diode is best understood through the us of a characteristic curve.
T
A capacitive diode is capable of being a constant voltage source because of the resistance changes that take place within the PN junction.
F
When a zener diode is rated at a specific voltage, it is not necessarily the same value of voltage that begins to cause the diode to break down.
T
A zener diode is designed to have a specific breakdown voltage rating.
T
The most popular zener diodes are those rated a 1 W larger.
F
A zener diode does not provide voltage regulation.
F
Load changes affect the zener diode as a regulator.
F
Always connect a ground between test equipment and a circuit with semiconductors before attempting to inject or monitor a signal.
T
