M4 Flashcards
1
Q
What is a semiconductor
A
Are elements or compounds which, under normal conditions, contain relatively few free (moving) electrons
2
Q
The most important elements that are used for semiconductor are
A
Silicon and Germanium
3
Q
At 0 degrees Kelvin a semi conductor is a
A
Non conductor
4
Q
When the temperature increases, an electron can be thrown off its atom and a positive charge remains which is called
A
Defect Electron or electron hole
5
Q
Electrons and electron hole permit the transport of
A
Charge
6
Q
The Conductive mechanism in a crystal is called
A
Bipolar
7
Q
What is a semiconductor diode
A
A kind of valve for electrical current. Allows only one flow of direction
8
Q
Consist of a semiconductive single crystal with a p-area and n-area.
A
Single Crystal Semiconductor diodes
9
Q
The process where impurities are deliberately added to create conductivity
A
Doping
10
Q
Threshold voltage of silicon
A
0.7
11
Q
Threshold Voltage of germanium
A
0.3
12
Q
Diode will only allow a current to flow completely through the junction at voltage above this level called
A
Threshold Voltage
13
Q
Is caused by residual impurities in the crystal and is due to the fact that heat waves cause crystal bonds to break down
A
Reverse Biased Current
14
Q
What will happen to semiconductor diode if the voltage in the direction of the depletion zone is too high, and depletion zone breakthrough occurs
A
destroyed
15
Q
Silicon monocrystals can handle temperatures of approx.
A
200°C
16
Q
Germanium monocrystals are destroyed at a temperature of
A
100°C
17
Q
How many amperes does a silicon permissible in forward biased currents
A
1000 amperes
18
Q
Maximum permissible reverse voltage for silicon diodes
A
5kv
19
Q
A type of single crystal semiconductor diode that are mainly used in communication technology. Their maximumforward biased current lies mostly far below one ampere
A
Microdiodes
20
Q
A type of single crystal semiconductor diode that are primarily used for electrical power supply devices.
Their maximum forward biased currents can be as much as 10 amperes
A
Rectifier Diodes
21
Q
A type of single crystal semiconductor diode that have maximum forward biased currents of approximately 10 to 1000 amperes. They are used in rectifier circuits for large power outputs
A
High Power Diodes
22
Q
A diode will show a ________ if wired in the reverse bias direction
A
very high resistance (open circuit)
23
Q
A diode will show a forward bias direction
A
very low resistance
24
Q
If the diode is faulty in the_______
then the reading will be high resistance or open circuit in both directions
A
Open circuit condition
25
When a multimeter is set to the diode test position it will supply a voltage sufficient to forward and reverse bias of diode. This voltage will be approx
2.5-3.5 volts
26
If the diode has failed and it show zero or nearly zero in both direction
short circuit condition
27
If the voltages to be blocked by the diodes exceed the maximum permissible reverse voltage of a diode, several diodes may be connected in
Series
28
Connecting diodes in this position is possible in general but has several limitations
Parallel
29
Diodes can be used to decouple electrical components
Decoupling Network
30
Diodes can also be used to short circuit the back emf that occurs when switching off relays
Free Wheeling
31
The main application of diodes is the usage as a
Rectifier
32
Transforms alternating current in direct current
Rectifier
33
Also called half wave rectifier. The most simple rectifier that only requires one diode
Single wave rectifier
34
A much better rectifier that supplies both half waves to the load but it needs a transformer with a double coil or tapped coil and two diodes
Full Wave Rectifier
35
A rectifier that also supplies both half waves. It requires 4 diodes for AC but six for 3 phase system. The diodes function as a Directional Signpost and also known as WYE rectifier
Bridge Circuits
36
Are used in brushless generators
Rectifiers
37
These units transform AC power to DC power with a lower voltage
Transformer Rectifier Unit
38
Are silicon diodes with a specifically defined steep breakdown in the reverse biased direction
Z diodes
39
States that after reaching a critical field strength, valence electrons are torn out of their lattice structure.
Zener effect
40
Zener effect is further supported by an
Avalanche effect
41
It shows a very steep curve, means that the dynamic resistance is especially small in the breakdown area
Z diodes
42
Are mainly used to regulate electrical voltage
Z diodes
43
Are important in all areas of electronics as sensors as well as visual signalling devices
Optoelectronic components
44
As the name statea, they are semiconductor diodes that emit light
LED
45
In LED, the colour of the light depends on the ______material that is used
Semiconductor
46
Are used for a variety of signalling and indicating purposes
LED
47
LED has a normal life span of
6 to 11 years
48
Are used for controlling devices in industry, for photoelectric beams and for monitoring manufacturing facilities and are also used in communication technology
Infrared LEDs
49
What is the polarity for LED
Forward biased direction
50
If the LED breakdown voltages in reverse direction are between 20 and 50 volts ,what is tbe switching times for red emitting light diodes
50 nanoseconds
51
If the LED breakdown voltages in reverse direction are between 20 and 50 volts, what is the switching times for green light emitting diodes
400 nanoseconds
52
In normal operation, the forward biased current of LED is somewhere between
5 mA - 40 mA
53
In normal operation, the forward biased current of LED is somewhere between
5 mA - 40 mA
54
Are semiconductors with a P-N junction that is exposed to light
Photodiodes
55
The polarity for this type of diode are always connected in reverse direction
Photodiode
56
If the P-N junction is illuminated, charges will be created in this area
Depletion Area
57
Photodiode characteristic in the amount of current in reverse direction is _______
to the amount of light
Proportional
58
Are no diodes, but they are made of semiconductor material
Light Dependent Resistor
59
Are semiconductor components without depletion zone, which change their effective resistance in accordance with an photoelectric effect
Light Dependent Resistor
60
In an electric circuit they behave like ohmic resistors, their resistance value is independent of the direction of current and they can be used in circuits with DC and AC
Light Dependent Resistor
61
Are especially useful for measuring low levels of illumination
Light Dependent Resistor
62
Are mostly used in LDR production
Cadmium, Lead and indium compounds
63
Are optoelectronic coupling elements used for transmitting signals while galvanic separating the input and output ports
Optical Coupling Devices
64
OCD contain at least one ______ on the input side and a ___ on the output
Transmitter Chip, Receiver Chip
65
A receiver that is most often used in OCD output side
Phototransistors
66
2 different types of phototransistors
Phototransistors with base and without base
67
LASCRs means
Light activated silicon controlled rectifiers
68
A coupling method where the light is reflected within the housing
Direct coupling
69
A coupling method where the light is reflected within a plastic coupling medium
Indirect Coupling
70
Insulation test voltages for OCD
between 4 and 15 kiloVolts
71
The insulation resistance of OCD is in the
Terra ohm region
72
It is called Varistor
Voltage Dependant Resistor
73
They are both no diodes but are made of semiconductor material
Voltage Dependant Resistor and Light
Dependent Resistor
74
The resistance level of varistor depends on the ____ that is applied
Voltage
75
The resistance of VDR decreases with the voltage_____
Increasing
76
Are chiefly used to protect systems against excess voltage
Varistor
77
They can also be used to regulate voltages and suppress interference in DC motors as well as for lightning protection and for protecting contacts against cut off currents in the case of inductors
Varistor
78
VDR consists of small highly conductive Zinc oxide particles that is covered with an extremely thin barrier that are
Sintered Together
79
Are fast electronic switches up to 10kHz and are diodes with control terminals or gates
Thyristor
80
They operate at voltages below the zero sweep voltage and can be switched from high resistance to low resistance by a change of voltage at the gate
Thyristor
81
Using this, very large currents and high power levels can be switched
Thyristor
82
Are constructed in four alternating layers, P-N-P-N, so that the three P-N junctions form between the layers
Thyristor
83
The transition from blocking mode to conducting mode takes place at certain voltage which is called the
Zero Sweep Voltage
84
If the thyristor is in low resistance state, a negative current applied to the control electrode will _____ return to its original high resistance state
Not
85
Thyristor in low resistance state can only return to its high resistance state if the electrical current falls a specific value called
Holding Current
86
In order to keep the thyristor from overheating, it must be
Cooled
87
The highest permissible voltages for thyristor are between
100 and 8000 volts
88
A Power supply which thyristors can controlled easily
DC
89
Thyristors also function as ______
because when they are oriented with a negative voltage at the anode, one half wave of the Alternating current cannot pass through
Rectifier
90
The control voltages are constantly released after a specific phase angle called
Ignition Delay Angle
91
The thyristor only lets a part of the positive half wave pass . Evey half wave is "cut into" this is called
Phase Angle Control
92
When the half wave rectifier is followed by a set of filters, the output voltage is
Smoothed
93
A triac or____ is in principle the wiring of two thyristors in an antiparallel circuits.
Bidirectional triode resistor
94
It is switched into low resistance mode by applying an electrical current to the control electrode in either direction
Triac
95
Triac has no cut off region but it does have a
Blocking region and gateway region
96
It can block current and let it pass in both directions of current flow, useful in regulating AC
Triac
97
Triac means
Triode Alternating current Switch
98
Today, they are only being built to take load currents of about 20A, so it is only possible to use them for medium range power outputs
Triac
99
Is used as a fast electronic switch or regulator for small and medium DC voltages and currents
Transistor
100
Three terminals of transistor
Emitter, base, Collector
101
If the arrow points outside the transistor it is a
NPN Transistor
102
The first layer emits charge carries called
Emitter
103
The middle layer or base region of the transistor. Its function is to control the emission of the charge carries
Base
104
The last layer that collect charges
Collector
105
Require the base voltage and the collector voltage to be positive in respect to the emitter
NPN Transistor
106
Require the base voltage and the collector voltage to be negative in respect to the emitter
PNP Transistor
107
The ratio of the collector current to the base current is called
Current Amplification
108
Normally only one voltage source is used to supply current to both the base emitter and collector emitter circuit. The voltage for the base is provided by
Voltage divider
109
Are arrangements of several electronic components in a common housing
Integrated Circuits
110
Its major advantage is the very high density of the components, the total arrangement therefore will be very contact
Integrated Circuits
111
They are quite resistant to mechanical stress and are very cheap
Integrated Circuits
112
The small housing and therefore the small surface is a disadvantage because some additional cooling might be required. To overcome this it must attached a
Heat sink or fan
113
A defective IC must always be
Replaced
114
Components that are integrated in ICs are
Transistors, diodes, resistors ,capacitors
115
Usually cannot be integrated due to their large space requirement
Inductors
116
They can be found in each and every modern appliance, in analouges as well as digital ones
ICs
117
Usually ICs are made from
very pure silicon
118
Consists of several amplifer stages
Operational Amplifiers
119
Is always a differential amplifier with two inputs and one output
Operational Amplifiers
120
Are manufactured using integrated technology and usually have very small dimensions
Operational Amplifiers
121
Can amplify both AC and DC
Operational Amplifiers
122
How many input terminals does an Operational Amplifiers have
two
123
An input terminal that is usually designated with a minus sign
inverting
124
An input terminal that is usually designated with a plus sign
Non inverting
125
Have been used primarily in analogue computers, which is where they get their name from
Operational Amplifiers
126
It can be created with Op amplifiers by using corresponding input and feedback networks
Electronic Voltage regulators
127
A regulator with a fixed ratio between input and output voltage (proportional)
P regulator
128
A regulator where the duration a voltage is applied to the input to determine the output voltage (integrator). Actual value of error
I regulator
129
A regulator where the change in input voltage will determine the output voltage (differentiator). Percentage error
D regulator
130
It was used since the 1970s and been popular medium installation of electronic components. They consist of a board, nowadays usually composites
PCB
131
Boards with several layers inside the board, up to 13 layers are used called
Multilayer Techniques
132
Two manufacturing process of PCB
Subtractive process and additive process
133
Are mainly used as components in electromechanical servo systems and positioning waves on a specific functional angles
Synchros
134
Two different types of servo systems
Open loop Systems and Closed loop Systems
135
The input position is converted to an electrical signal and this demand signal is amplified and sent to the motor to position the load. This is unsuitable for close tolerance use
Open Loop System
136
The signal is sent from the input, through the amplifier to the output motor and the load just as in the open loop system.
Closed Loop system
137
The difference between the actual position and demanded position is called
Error signal
138
The signal of output position which is sent back to the comparator is referred to as
feedback signal
139
A servo system where the rotor of the receiver follows the rotor of the transmitter is also referred to as
Follow up
140
Its application is to add or subtract angles. It has 3 coils wired in a star connection on the rotor, which has a circular cross section so it does not influence the magnetic field of the stator
Differential Transmitter
141
Have coils in the stator and the rotor which are displayed by 90 degrees from each other. It can be used just like a control synchro for transmitting angles
Resolver
142
LVDT means
Linear Variable Differential Transformer
143
Is used to transfer linear movements but also angular movements such as rudder deflections
LVDT
144
Configurations which vary the coupling of the primary coils with the secondary coils by rotating the iron core are known
RVDT
145
RVDT means
Rotating Variable Differential Transducers
146
Its principle can be used to measure position or speed of a component
Inductance transmitter
147
Arrangement for inductance transmitters often referred to as
Proximity Switch
148
Its principle can be used as a method of measuring fuel level
Capacitance transmitter
149
It is a component which can hold a charge on two plates separated by a material known as DIELECTRIC
Capacitor
150
It shows what happens in the forward area.
Curve
151
Do not block an electrical current one hundred percent
Semiconductor diodes
152
Maximum permissible reverse voltage for germanium
Must be less than 200v
153
Different names of microdiodes
Junction diodes, point-contact or planar diodes
154
Breakdown voltage of z diodes especially good properties
5-7v
155
Breakdown voltage of z diodes
2.7v up to 100v
156
The power for the rotating field is induced by the
Exciter generator
157
Resulting current is rectified by
Rotating diodes
158
Breakdown voltages in the reverse direction of LED
20-50v
159
Forward bias voltage of an LED
1.4v and 4.5v
160
LDR they can handle voltages anywhere from
20v to 300v
161
Much higher current amplification can be achieved using
Darlington transistors as receivers
162
Permissible ampere of thyristor
3A (mircrothyristor) and 4500A (macrothyristor)
163
Phase control produce
Harmonic oscillation
164
Unchanged properties
Intrinsic Conductivity
165
If the voltage in the direction of the depletion zone is too high, a depletion zone breakthrough occurs and in most cases the semiconductor diode will be destroyed
Peak Inverse Voltage
166
In measuring forward bias the measured voltage is the?
Threshold Voltage
167
In measuring reverse bias the voltage measured is the
Internal voltage of the meter
168
Diodes in series the measured voltage is lower or higher
Lower
169
Diodes in parallel the measured current is lower or higher?
Higher
170
Only allow light to reach the surface because the underlying gallium arsenic substrate is opaque
Red LED
171
Consist of three sequential semiconductor layers
Transistor
172
Has two P-N junction where depletion layers form like in diodes
Transistor
173
Are usually supplied with both a positive and negative operating voltage
Operational amplifiers
174
The ideal operational amplifier has
• amplification which is nearly infinite
• Input resistance which is almost infinite
• Small output resistance
• Input voltage of approximately zero volts
175
Boards are used that are not laminated with copper
Additive process
176
Boards laminated with copper on one or both sides are used
Subtractive process
177
Are similar in construction to alternating current generators
Synchros
178
Are manufactured with a diameter of 0.5 and 3.7 INCHES
Synchros
179
Work likes a three phase transformers
Synchros
180
Operate with analogue voltages and currents they are analog transducers
Synchros
181
2 types of syncros
Torque Synchros & Control Synchros
182
works like a chain / generate torque
Torque synchro
183
output is voltage / does not generate torque
Control synchro
184
It delivers a voltage which depends on the differential angle between the transmitter rotor and receiver rotor
Control synchros
185
If both shafts are turned in the same direction what is the result?
subtraction
186
If the shafts are rotated in opposite directions
Addition
187
TORQUE TRANSMITTER
TX
188
TORQUE DIFFERENTIAL TRANSMITTER
TDX
189
TORQUE DIFFERENTIAL RECEIVER
TDR
190
TORQUE RECEIVER
TR
191
CONTROL TRANSMITTER
CX
192
CONTROL DIFFERENTIAL TRANSMITTER
CDX
193
CONTROL TRANSFORMER
CT
194
RESOLVER TRANSMITTER
RX
195
RESOLVER DIFFERENTIAL TRANSMITTER
RDX
196
RESOLVER TRANSFORMER
RC
197
Larger rotation moments are required than a torque synchro chain
Servo system
198
Transmitter and the receiver are electrically and mechanically identical
Torque synchro
199
happens when there is a differential angle between Transmitter rotor and the receiver rotor
Torque moment
200
happens when the voltage in the direction of the depletion zone is too high
Peak Inverse Voltage
201
rotor axis is aligned with the axis of the stator coil
Rotor Angle
202
Heats the semiconductor crystal
Maximum Forward current
203
has the form of a sine wave
Excitation Voltage
204
used as components in electromechanical servo Systems
Synchro
205
Forward current exceed the max forward Current of individual diode, diode will explode
Diodes in Parallel
206
collector base diode is in the blocking direction
Collector/Emitter Voltage
207
allows the light to reach the surface
RED LEDS
208
diodes with control terminals or gates
Thyristors
209
achived by means of reverse coupling
Dampening
210
what external connection will be used to determine the function of the circuit
Negative FeedBack
211
used to isolate electrical components
decoupling Network
212
What do you call the maximum voltage that can be applied to a diode and once exceeded can damage a diode?
Peak inverse voltage
213
What is the use of a rectifier on a brushless generator?
Exciter Generator
214
Junction of a transistor that can be controlled
Between base emitter junction
215
Similar in construction to alternating cu generators manufacture with a diameter between 0.5 and 3.7 inches?
Synchros
216
Used to split an input angle into its sine and cosine components?
Resolver
217
What is the difference of a thyristor to a transistor?
Latching, thyristor only has latching while transistor don't have.
218
Principle wiring of two thyristor, one crystal have common junction
TRIAC
