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The collector handles huge currents as well as connected to High potential(i.e. Vcc). So It is handling very high power. In order to dissipate this power the area should be large according to Stefen's law of radiation.
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Why collector is made larger than base and emitter in a transistor?
Collector has larger area than base and emitter because base collector is reverse biased, hence the current flow here due to the minority carriers and the large power dissipation takes place by the majority carriers, this power dissipated in the form of heat.. To cool the device from heat we made the larger area........
Why is the base of transistor made very thin?
Base of transistor is made thin just to get Collector current equal to Emitter current.
Working of npn transistor?
N-p-n transistor is made by sandwiching thin layer of p-type semiconductor between two layers of n-type semiconductor. It has three terminals, Emitter, Base and collector. The npn transistor has two supplies, one is connected through the emitter base and one through the collector base. The supply is connected such that emitter-base are forward biased and collector base are reverse biased. It means , Base has to be more positive than the emitter and in turn, the collector must be more positive than the base. The current flow in this type of transistor is carried through movement of electrons. Emitter emits electrons which are pulled my the base as it is more positive. these end up in the collector as it is yet more positive. In this way, current flows in the transistor. Transistor can be used as an amplifier, a switch etc.
What are the characteristics of a CB amplifier?
it is a mode of amplifier connection where the base part of the transistor is made common to both input and output.the circuit diagram is as shown below. the transiator gain(represented by the greek letter beta-B) is usually evaluated by the formula B=output current divided by input current. as we know that when the transistor is connected in common base mode the input pert will be emitter and the output part will be collector and we know that the collector current is quiet less than emitter current. as per the formula gain will be less than one. practically we consider emitter current as equal to collector current and hence B approaches 1 in case of common base mode amplifiers.as the gain is very less it is very less used as amplifiers. generally they use common emitter mode for amplification as this mode optimum amount of amplification.
What are the operating regions of transistors and explain it?
There are three operating regions in transistor...(Transfer-Resistor)1)cutoff region2)Active region3)Saturation regionActive region:It is the central region where there are curves and where slope is taken.it is the region where emitter-base is forward biased and collector-base is reversed bias.Cutoff region:It is the region which lies below the curves. it is the region where the transistor is in OFF state.in this region both emitter-base and collector-base is reversed bias(i.e no sufficient voltage is applied so that the voltage does not break the DEPLETION region).Saturation region:It is the region situated to near the active region near Y-axis.It is the region in which the both emitter-base and collector-base is forward biased.Based on application the transistor is decided where to lie.for example transistors are made to lie in active region to make it as amplifier.when transistors are used as switch it is made to lie in saturation region(when switch is made as ON) and cut-off region(when switch is made as OFF).....Thanks guys for reading this. please forgive me if there are any mistakes....ANSWER: In actuality there is only one REGION The other regions are not operating regions but rather states. An operating region on a transistor is set up during design of an amplifier to transfer maximum undirstorted power to the load. This design is called BIAS
Why is collector wider than emitter and base?
actually in the case of transistors there are two concepts that are often misleaded those are 1. order of doping 2. order of the size of various regions order of doping emitter>collector>base order of size of various regions collector>emitter>base now the reason for this as CB junction is reverse biased more heat is dissipated at this junction so if the collector junction has large area the heat can be dissipated easily there by the transistor is saved from the burning of CB junction
Why collector is made larger than base and emitter in a transistor?
Collector has larger area than base and emitter because base collector is reverse biased, hence the current flow here due to the minority carriers and the large power dissipation takes place by the majority carriers, this power dissipated in the form of heat.. To cool the device from heat we made the larger area........
Why is the base of transistor made very thin?
Base of transistor is made thin just to get Collector current equal to Emitter current.
What elements make up transistors?
The 3 imp parts of Transistors are its Emitter, collector and Base
Working of npn transistor?
N-p-n transistor is made by sandwiching thin layer of p-type semiconductor between two layers of n-type semiconductor. It has three terminals, Emitter, Base and collector. The npn transistor has two supplies, one is connected through the emitter base and one through the collector base. The supply is connected such that emitter-base are forward biased and collector base are reverse biased. It means , Base has to be more positive than the emitter and in turn, the collector must be more positive than the base. The current flow in this type of transistor is carried through movement of electrons. Emitter emits electrons which are pulled my the base as it is more positive. these end up in the collector as it is yet more positive. In this way, current flows in the transistor. Transistor can be used as an amplifier, a switch etc.
Why two diode join cant act as transistor?
No, it is not possible because in transistor the depletion layers formed in Emitter-Base Junction & Collector-Base Junction are penetrable by both current carriers but in this case of two diodes; the formed depletion region are not penetrable for current carriers (hole &electron). Also, a transistor works only because the base layer is very thin. You won't get that thin layer between emitter and collector just by connecting two diodes together. This thin base layer places the Emitter and Collector in very close proximity to each other. This allows majority carriers from the emitter to diffuse as minority carriers through the base into the depletion region of the base-collector junction, where the strong electric field collects them. In other words the emitter/base current flow draws some of the barrier charge away from the collector/base junction and allows collector/emitter current to flow across the base using minority carriers. So transistor action is not possible. But we can make transistor by connecting two diodes and two dependent current sources i.e. Ebers-Moll model of transistor. This is true only when you want to make the transistor act like a on/off switch, but you cannot make this setup of diodes to act like an amplifier. Whereas the transistor also acts as an amplifier too A transistor can act as: (1) on/off switch (2) amplifier. Diode is made up of two layers and one junction. Transistor is made up of three layers and two junctions.
Why does the collector has larger area in the transistor?
collector has larger area than base and emitter because base collector is reverse biased hence current flow here due to minority carriers and the large power dissipation take place by the majority carriers this power dissipated in the form of heat. to cool the device from heat we made the larger area.
What pnp friendly means?
Since this is in the electronics section, I'll assume you mean a PNP transistor. PNP refers to the semiconductor layers used to make up the transistor. The P and N letters refer to positive and negative doping in the semiconductors, which changes the way electrons flow through the layers. This is a bipolar junction transistor (BJT), which can be thought of as a current amplifier. One P layer is called the emitter and the other is called the collector. The N layer is called the base. The emitter and collector are not usually interchangeable because they are made differently. When the voltage on the base is below the voltage on the emitter, usually by about 0.7 Volts, current flows from emitter to base. This allows a much larger current to flow from emitter to collector. This assumes the collector is at a lower voltage than the base, and is the usual connection. Similarly, there are NPN transistors.
What are the characteristics of a CB amplifier?
it is a mode of amplifier connection where the base part of the transistor is made common to both input and output.the circuit diagram is as shown below. the transiator gain(represented by the greek letter beta-B) is usually evaluated by the formula B=output current divided by input current. as we know that when the transistor is connected in common base mode the input pert will be emitter and the output part will be collector and we know that the collector current is quiet less than emitter current. as per the formula gain will be less than one. practically we consider emitter current as equal to collector current and hence B approaches 1 in case of common base mode amplifiers.as the gain is very less it is very less used as amplifiers. generally they use common emitter mode for amplification as this mode optimum amount of amplification.
What are the operating regions of transistors and explain it?
There are three operating regions in transistor...(Transfer-Resistor)1)cutoff region2)Active region3)Saturation regionActive region:It is the central region where there are curves and where slope is taken.it is the region where emitter-base is forward biased and collector-base is reversed bias.Cutoff region:It is the region which lies below the curves. it is the region where the transistor is in OFF state.in this region both emitter-base and collector-base is reversed bias(i.e no sufficient voltage is applied so that the voltage does not break the DEPLETION region).Saturation region:It is the region situated to near the active region near Y-axis.It is the region in which the both emitter-base and collector-base is forward biased.Based on application the transistor is decided where to lie.for example transistors are made to lie in active region to make it as amplifier.when transistors are used as switch it is made to lie in saturation region(when switch is made as ON) and cut-off region(when switch is made as OFF).....Thanks guys for reading this. please forgive me if there are any mistakes....ANSWER: In actuality there is only one REGION The other regions are not operating regions but rather states. An operating region on a transistor is set up during design of an amplifier to transfer maximum undirstorted power to the load. This design is called BIAS
What properties make the transistor so useful in the digital age?
transistors are basically made of semi conductors,it consist of two p-n junctions and is divided in 3 parts emitter, base and collector. It has three terminals connected to each of them, because of transistors current contolling capacity in circuit they can be used as oscillators and switches.
What are common uses of a common emitter amplifier?
bcause amplification factor beta is usually ranges from 20-500 hence this configuration gives appericiable current gain as well as voltage gain at its output on the other hand in the Common Collector configuration has very high input resistance(~750 kilo ohm) & very low output resistance(~25 ohm) so the voltage gain is always less than one & its most important application is for impedance matching for drivingh from low impedance load to high impedance source
