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In NPN transistor, Base is connected to positive terminal of battery.
Now, when current is switched on, Base-Emitter junction (indicated in image) is forward biased, whereas Base-Collector junction is reverse biased.
Remember that forward bias narrows depletion region, whereas reverse bias widens depletion region.
n-type region(lower one) on emitter side has majority electrons (reason 'n' stands for negative).
These electrons move from emitter side to base.
Base is thin region, which has holes. When electrons move from emitter to base only a few electrons combine with holes. Whereas others pass from base to collector.
In collector the electrons are pulled by positive terminal of battery(right hand side battery). And thus the cycle of current continues to flow.
That is whole working of NPN transistor.
Wiki User
∙ 8y ago
Wiki User
∙ 13y agoIn the early days PNPs worked better than NPNs which made them very popular in designs at higher frequencies and faster switching speeds. Now they work worse because the mobility of electrons is 3x higher than holes and NPN technology has improved. There are many situations where they work well. One is in a direct coupled amplifier of alternating types. Another is for high side switching.
Wiki User
∙ 11y agoBasically for the same things as pnp transistors - to amplify signals, and to do switching tasks in circuits.
Wiki User
∙ 13y agoThe polarity and biasing is exactly opposite.
Wiki User
∙ 10y agoThat means that it has three layers, with n-type, p-type, and n-type material in that order.
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What is difference between npn ans pnp transistor?
NPN and PNP transistors function in essentially the same way. The power supply polarities are simply reversed for each type. The only major difference between the two types is that the NPN transistor has a higher frequency response than the PNP-because electron flow is faster than hole flow. Therefore high frequency applications will utilize NPN transistors.
Is the pnp transistor in common collector can be replaced with npn transistor?
No. The PNP and NPN transistors are exactly opposite each other in polarity. You cannot just replace one for the other without redesigning the circuit.
How many pn junction does transistor contain?
Two, either in NPN or PNP transistors
What is the major difference an NPN transistor and a PNP transistor?
The NPN transistor has its conduction curve where the base is more positive than the emitter, while the collector is also more positive than the emitter. The PNP transistor is exactly opposite, with its conduction curve where the base is less positive than the emitter, while the collector is also less positive than the emitter.
Is bipolar transistor is made up of one NP junction?
no, 2 junctions. NPN or PNP
Difference between NPN and PNP?
NPN and PNP are transistor types. The difference in the way the layers of semiconductor material are doped with impurities.
What is the difference between npn and pnp transistor in the application?
There is no difference they perform the same functions.
What is difference between npn ans pnp transistor?
NPN and PNP transistors function in essentially the same way. The power supply polarities are simply reversed for each type. The only major difference between the two types is that the NPN transistor has a higher frequency response than the PNP-because electron flow is faster than hole flow. Therefore high frequency applications will utilize NPN transistors.
What are the functions and empowerment of PNP as per PNP laws?
pnp and npn transistor
Is BT169 a npn or pnp transistor?
BT169 is neither an NPN nor a PNP transistor. BT169 is a thyristor, otherwise known as a silicon controlled rectifier.
Can be replace npn transistor series regulator with pnp?
no
How do you know if a transistor is a PNP or an NPN?
To know if a transistor is PNP or an NPN,the following should be verified:For a PNP transistor, the base-collector junction is forward biased while the base-emitter junction is reversed biased.For an NPN transistor, the base-emitter junction is forward biased while the base -collector junction is reversed biased.
Why npn transistor preferred according to fabrication technique?
npn is preferred to pnp since n-doping can be pushed to higher values without damaging silicon lattice. due to this fact, doped regions can be less resistive. difference between npn and pnp is becoming smaller and smaller, tho.
Field-effect transistor NPN or PNP?
NPN, PNP only classified to BJT, while FET classified as P-channel , N-channel
How is the NPN transistor different from the PNP transistor?
"P" is for Positive and "N" is for Negative So basically put a PNP Transistor Would use N to Switch P, in the name "PNP" or "NPN" the first character is for the polarity of the Collector-pin, the second for the Base-Pin, and the third for the Emmiter-pin. So if you have a PNP Transistor you can`t just replace it with an NPN as the polarities differ. If you can find a way to change those polarities then sure it could work. The Collector-pin basically receives the bigger current. The Base-pin determines how much of that current will be transferred to the emmiter-pin. So in a PNP the base current could for example be 0V and the Collector 5V, this will allow a free flow of current from Collector to Emmiter, the usage of a transistor in many cases is to switch high current with lower current. The main difference is that a PNP transistor uses "holes" as carriers and an NPN transistor uses electrons as carriers (It is to be remembered that the flow of current is always in the direction opposite to that of the flow of electrons). The difference in the symbol for the two transistors are that the PNP transistor will have an arrow pointed to the base from the emitter, and the NPN has it pointing outside.
Is the pnp transistor in common collector can be replaced with npn transistor?
No. The PNP and NPN transistors are exactly opposite each other in polarity. You cannot just replace one for the other without redesigning the circuit.
Transistors Basic material of?
silicon ang germanium there are two types of transistor \ 1. PNP 2. NPN silicon ang germanium there are two types of transistor \ 1. PNP 2. NPN
