industrial electronics test 3
when a transistor is driven into saturation, how much voltage is dropped across the collector-emitter section?
.3v
When a silicon transistor is considered to be completely turned on, how much voltage is dropped across the collector-emitter section?
.7v
A transistor is connected into a circuit as an amplifier. The power supply furnishes 12 volts to the transistor. When biasing the transistor, how much voltage should be dropped across the collector-emitter section of the transistor?
1/2(12) so 6
What is the most common system used in the identification, of transistors?
2N registry
How many layers of semiconductor material are required to make a transistor?
3
a Darlington amplifier circuit, a base current of 15 microamperes (uA) causes a current of 100 milliamperes (mA) to flow through the circuit. What is the gain of this circuit?
B=100mA/15uA equals 6666.67
Darlington amplifier circuit has a beta of 5000. The power transistor must have a collector-emitter current of 1.5 A What is the minimum amount of base current that can be applied to the driver transistor?
IB= Ic/B 1.5a/5000 is 300ųA
Why is it desirable to drive a transistor into saturation when it is used for switching?
It reduces the power requirement for the transistor
Nhat are the two major types of transistors?
NPN and PNP
why is it necessary to bias a transistor when it is to be used as an amplifier?
To prevent the output wave form from being clipped or cutoff
When an NPN transistor is to be tested with an ohmmeter, does the transistor appear to be two diodes with their anodes connected together or their cathodes connected together?
anodes connected together
what greek letter is used to represent the gain of a transitior in a circuit?
beta
When a transistor is in a standard TO3 case, which lead is connected to the case of the transistor?
collector
when a transistor is in a standard TO5 package, which lead is located closest to the metal tab on the case of the transistor?
emitter
When a transistor is to be used as an amplifier, it must be baised, explain how to.
midpoint bias vc=1/2vcc
why is silicon used more often than germanium in the production of transistors?
not as influenced by thermal runaway(purple plague)
What does the word bias mean?
preset condition of the Voltage (polarity and magnitude)
How is a transistor driven into saturation?
providing more current to the base than needed for normal operation
What is the disadvantage of driving a transistor into saturation?
reduces the frequency response so can't switch as fast
How is a darlington amplifier constructed?
the emitter of one transistor is connected to the base of another transistor
in a Darlington amplifier circuit, what is the "driver transistor"?
the transistor that feeds the base of the power transistor.