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How many volts do you need for a transistor to be fully on?
A: By saturating a transistor meaning forward bias the base to emitter the voltage across the collector and base should be very low . depending on current it can be .050 v to .5v reversing or removing the bias voltage this voltage should be the same as the rail
How the current flow through npn?
A; The base must be positive with respect to the emitter this condition will allow collector current to flow from collector to emitter. If the transistor manage to get saturated the current can flow in both direction. as a switch
What elements make up transistors?
The 3 imp parts of Transistors are its Emitter, collector and Base
What is saturation and decline stage?
saturation and decline of the supermarket
An object is a good emitter of radiation if it is what?
An object is a good emitter of radiation if it is a good absorber of radiation.
What is Saturation voltage of bjt?
It is the CE (collector - emitter) voltage at a given collector current when the transistor is fully on. Increasing the base current will not lower the CE voltage any more once saturation has been reached.
What should be the value of collector current in terms of DC gain if transistor is in saturation mode?
DC current gain is collector-emitter current divided by base-emitter current. In linear mode, gain is beta, or hFe. In saturation mode, however, the transistor is over-driven and you can no longer relate collector-emitter current to base-emitter current. The transistor operates like a switch, and collector-emitter current is a function of voltage and load impedance only. (Ignoring the relatively small voltage drop.) To maintain saturation mode, the collector-emitter current must be smaller than the base-emitter current times hFe. Often, it is several times smaller, because hFe can vary from transistor to transistor, and your design must account for this variability.
What arer the 3 legs of a transistor?
Emitter, Collector and Base cutoff region, saturation region, and liner region
What does it mean when you say a transistors junction is saturated?
It's called saturation because the collector voltage cannot go any lower. You've done all you can do with your base current (in Common Emitter configuration) to lower the collector voltage and support the collector current.
Why we kept VOLTAGE collector to emitter half of voltage vcc?
We bias the common emitter amplifier to have a collector-emitter voltage of one half of Vcc in order to set the operating point halfway between the two extremes.
Explain why the collector voltage is approximately zero when a transistor has a collector-emitter short?
The collector voltage is not necessarily approximately zero when a transistor has a collector-emitter short. It depends on whether or not there is an emitter resistor.A typical collector-emitter circuit has two resistors, one in the collector and one in the emitter. One or both of them might be zero, i.e. not present, depending on design requirements. The collector-emitter junction represents a third resistor, the value of which is dependent on base-emitter vs collector-emitter current ratios and hFe.If the collector-emitter junction is shorted, then this circuit degrades to a simple voltage divider, or single resistor, and the collector-emitter voltage differential will be approximately zero. Simply calculate the voltage based on the one or two resistances.Results could be different than calculated, if the resistors are small in camparision to the shorted impedance, and it could be different depending on the base to emitter or collector relationship in that fault state, though the latter case is usually negligible due to the relatively high resistances of the base bias circuit.
Explain the saturation region in common emitter transistor?
A: As base current increases the collector current increases to a point where any more base current will not increases the collector current at hat point the transistor is saturated whereby current may flow in both direction and the two diodes will essentially be in a parallel mode and the voltage drop from emitter to collector will reflect the status as a low voltage drop.
What does the electronic term Vb mean?
Base voltage in a transistor. There is also Vc (Collector voltage), Ve(Emitter voltage), Ic(Collector current), Ib(Base current), Ie(Emitter current), Vcc(Supply voltage), and Hfe (Forward current gain)
How transistor produce 180 degree phase shift?
In the common emitter configuration, a class A amplifier, an increase in base voltage (the input) leads to an increase in base-emitter current which leads to a proportionately larger increase in base collector current. That pulls the collector towards the emitter, which decreases the collector voltage. Since the collector is the output, this configuration is an inverting amplifier.
Why in common collector amplifier however you change value of resistance not amplifier in voltage?
The question does not quite make sense. It sounds like you are asking why does changing the emitter resistor in a class C common collector amplifier not affect the output voltage? If so, the answer is that the common collector is an emitter follower, meaning that the emitter will follow the base, less the base-emitter junction voltage, within the limits of hFe. The resistor is simply there to ensure output biasing when the base voltage goes low.
Why is collector current increased slowly with the increase of collector to emitter voltage of a common emitter?
The percentage of doping in emitter is higher than collector region.hence large current is flow to emitter than collector.
Why there is 180 degrees phase shift in common emitter amplifier?
In the common emitter amplifier, an increase of base-emitter current causes a larger increase of collector emitter current. This means that, as the base voltage increases, the collector voltage decreases. This is a 180 degree phase shift.
