It all depends which lead is connected to the common power supply, Emitter, base or collector.
For most amplification needs using NPN transistors, common emitter is used.
Other applications are used for current control and regulation circuits.
it is one of the configuration of BJT ,which is achieved by making the BASE grounded(i.e common base).Here the emmiter serves as the input and collector as the output.
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.
its the simplest thing to do. There are three legs in a transistor, one each of collector, base and emitter. So if you need to use it as a diode, just connect either collector-base or emitter-base. Say, if you use an NPN transistor, then the base region will be the anode of diode and emitter or collector will be the cathode of the diode.
The percentage of doping in emitter is higher than collector region.hence large current is flow to emitter than collector.
In whch emitter is cmmön.input is taken frm base nd output is obtaind acros collector.
A circuit in which the input signal is applied to its base and the collector is earthed (grounded) is known as common collector configuration of BJT (BiPolar Junction Transistor)
Common base transistor if the emitter is open current Ie=0 but a small collector current thus exist.this current is reversed biased collector to the base voltage it is represented by Icbo while common emitter is d base terminal is open circuit and the base junction is reversed biased current Icbo flow from the tcollector to the emitter in the external circuit this current is called leakage current.
from the name itself the common collector has its collector terminal in common with both the input and output circuits of a transistor and the base current is chosen as the input current and the output current is the emitter current
The base.
The transistor has three regions, emitter,base and collector. The base is much thinner than the emitter while the collector is wider than both. However for the sake of convenience the emitter and collector are usually shown to be of equal size. The transistor has two pn junctions that means it is like two diodes. The junction between emitter and base may be called emitter-base diode or simply the emitter diode.The junction between base and collector may be called collector-base diode or simply collector diode. The emitter diode is always forward biased and the collector diode is always reverse biased.
In a common emitter amplifier, the base-emitter current causes a corresponding collector-emitter current, in the ratio of hFe (beta gain) or collector resistance over emitter resistance, which ever is less. Since this ratio is usually greater than one, the differential collector current is greater than the differential base current. This results in amplification of the base signal. As you increase the base-emitter current, the collector-emitter current also increases. This results in the collector being pulled towards the emitter, with the result that the differential collector voltage decreases. This results in inversion of the base signal.
it is one of the configuration of BJT ,which is achieved by making the BASE grounded(i.e common base).Here the emmiter serves as the input and collector as the output.
the bass word is collect
No. For BJTs, they have a natural amplification, B, of current between the base current to collector current. In rough calculations, I've often used 50. So applying 20uA of current to the base of a BJT should cause 1mA of current to flow through the collector (assuming base, collector, and emitter resistors are sized appropriately so this is not limitted). The emitter will see the base current + the collector current.
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.
there are 3 types of configuratons......they are 1.common emmiter configuration 2.common collector configuration 3.common base configuration
1st pin is emitter then collector and base