Why emitter current is greater than collector current?
The base contains more holes than electrons. As the direction of current is opposite to the flow of electrons we can understand that current from the emitter is conducted to the base and the collector. Hence, the collector current will always be slightly less than the emitter current.
Why is Collector current less than emitter current in BJT?
Some of the electrons combine with the majority charge carrier holes present in the base and most of the electrons reach the collector, crossing the collector-base junction. This implies that collector current is always less than the emitter current due to the reason (b).
Why is Collector wider than emitter in BJT?
The collector region is the largest of all regions because it must dissipate more heat than the emitter or base regions. It is designed to be large because in order to dissipate all the heater, the extra surface area allows it to do so. The larger area ensures that it has more surface area to dissipate heat.
What happens to collector current when base current is increased?
As the base current increases the collector increases proprtionally till the operating point reaches the boundary between the active region and the saturation region. At this point the collector current will be equal to collector saturation current.
What’s the difference between a common emitter and a collector?
In common emitter (CE) configuration, input current or base current is denoted by I B and output current or collector current is denoted by I C. The common emitter amplifier has medium input and output impedance levels. So the current gain and voltage gain of the common emitter amplifier is medium. However, the power gain is high.
What happens to a transistor in a common collector configuration?
In common collector configuration, if the input current or base current is zero then the output current or emitter current is also zero. As a result, no current flows through the transistor. So the transistor will be in the cutoff region. If the base current is slightly increased then the output current or emitter current also increases.
What is the output voltage of a common collector?
The input supply voltage between base and collector is denoted by VBC while the output voltage between emitter and collector is denoted by VEC. In this configuration, input current or base current is denoted by IB and output current or emitter current is denoted by IE.The common collector amplifier has high input impedance and low output impedance.
What is the ratio of base current to emitter current in a transistor?
The ratio of change in collector current (ΔI C) to change in base current (ΔI B) is defined as the current gain of common emitter transistor. In a bipolar junction transistor, the emitter current (I E) is the sum of the base current (I B) and collector current (I C ).