From this characteristic curve we can infer that for fixed value of Output Voltage (VLaxmi is a B.E (Electronics & Communication) and has work experience in RelQ Software as Test Engineer and HP as Technical support executive. In this bipolar junction transistor, the voltage across the emitter-base junction (that is in forward-bias) is always less than the collector-base junction (reversed-bias). similarly, when the switch is ON, the current will flow through the circuit and act as a close circuit.The transistor is nothing but a power electronics switch that can work like normal switches. Working of PNP Transistors: As discussed above, the transistor is a current controlled device which has two depletion layers with specific barrier potential required to diffuse the depletion layer. The structure is opposite to NPN transistor but similar in operation.The PNP Transistor symbol shows an arrow pointing inwards from Emitter to the Base which indicates the direction of the conventional current flow. So, Base voltage is a minimum of 0.7 V in reverse bias to conduct the transistor.It means that, if the Base voltage is zero or less than 0.7 V, the current cannot flow and it acts as an open circuit.To turn ON the transistor, the Base voltage must more than 0.7 V. In this condition, the transistor acts as a close switch.The main differences when comparing PNP transistors vs NPN transistors have been summarized in the table below:Electrical4U is dedicated to the teaching and sharing of all things related to electrical and electronics engineering.We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites. In PNP Transistors the electrons are minority charge carriers and holes are majority charge carriers.
Now the question is how can we use PNP transistor as a switch?As we have seen in the working of the PNP transistor, if the Base voltage is not more negative then Emitter voltage, the current cannot flow through the device.
The Collector region collects most of all charge carriers emitted from the Emitter. The emitter terminal is formed by P-type semiconductor thus, for forward biasing the P-type terminal should be connected with positive terminal and N-type with negative terminal.
So, Base voltage is a minimum of 0.7 V in reverse bias to conduct the transistor.
She is an author, editor and partner at Electricalfundablog.PNP Transistor – Working Principle, Characteristics & ApplicationsInput Characteristics for Common-Base ConfigurationOutput Characteristics for Common-Base Configuration It means that, if the Base voltage is zero or less than 0.7 V, the current cannot flow and it acts as an open circuit.
This type of switching is used for negative ground configurations. It also implies that reducing forward bias voltage decreases the current flow.The relationship between DC currents and voltages are represented graphically, which are known as characteristics. So, it is necessary to give a voltage source in reverse bias more than 0.7 V.In general, when the switch is OFF, the current cannot flow and behaves as an open circuit.
The Collector current (IThe circuit of the PNP transistor is as shown in the below figure.If we compare the circuit of PNP transistor with NPN Simultaneously, very few electrons enter in Emitter from the base and recombine with the holes.The loss of holes in the emitter is equal to the number of electrons present in the Base layer. These holes constitute the emitter current.
P type semiconductor contains holes and This holes going to transfer to the base.
Therefore, a very large number of holes from emitter cross the depletion region and enter the Base. Working of NPN Transistor. Fig. PNP Transistor is a sub-type of Bipolar Junction Transistors (BJT’s).
transistor, then here the polarity and direction of current are reversed.If a PNP transistor is connected with voltage sources as shown in the above figure, the base current will flow through the transistor.
The arrowhead shows that the current will flow through Emitter to Collector.Due to this type of bias, the depletion region at Emitter-Base junction is narrow, because it is connected in forward bias.
The two important characteristics of a PNP Transistor are:In Common-Base Configuration, for various constant values of Output Voltage (VThe figure below shows approximated plot for Input Characteristics.
Electrons travel slowly in a semiconductor and holes move more slowly than electrons.
It is a basic transistor and often used in various electronic circuits.