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What is the current gain of a PNP transistor?
For example a BC109B has a current gain h FE between 200 and 450, and a BC109C has a current gain h FE between 420 and 800. Whatever the circuit used, and whether NPN transistors or PNP transistors are used, the current gain of the transistor is a key parameter.
How is the gain of a transistor calculated?
Transistor gain & Beta, β When undertaking many calculations the transistor current gain is given in terms of the Greek letter Beta; β. This is the forward current gain for the transistor when operated in a common emitter mode. Basic transistor current flows
Where is the arrow located in a PNP transistor?
The arrow for BJT transistors is always located on the emitter terminal and also it indicates the direction of conventional current flow. In PNP transistor this arrow indicates as ‘pointing in’ and the current direction in PNP is completely opposite to the NPN transistor.
Why is the gain of a bipolar transistor important?
In any circuit, the current gain of a bipolar transistor will be of paramount importance. Whether the circuit is common emitter, common collector, etc, and whether it uses NPN transistors or PNP transistors.
What do you need to know about bipolar NPN transistors?
One other point to remember about Bipolar NPN Transistors. The collector voltage, ( Vc ) must be greater and positive with respect to the emitter voltage, ( Ve ) to allow current to flow through the transistor between the collector-emitter junctions.
How are negative electrons used in a NPN transistor?
So in a NPN Transistor it is the movement of negative current carriers (electrons) through the Base region that constitutes transistor action, since these mobile electrons provide the link between the Collector and Emitter circuits.
For the common base transistor, current gain equals the ratio of collector current to that of the emitter current. Let us consider a PNP transistor which is a part of some electronic circuit. The given parameters are the base voltage, emitter voltage, and the supply voltage.
Is the PNP transistor the same as fig?
The symbol of the PNP transistor is the same as fig. One thing to note here is the current direction in both NPN and PNP transistors. This helps a lot while solving numerical problems. The circuit connection of the PNP transistor is as below. Here the emitter region has a positive bias voltage with respect to base and collector.
How are pn junction diodes connected in a PNP transistor?
The PNP transistor acts as two PN junction diodes connected one after another. These diodes make junctions as are connected one after another and are called collector-base and base-emitter junction. In PNP transistors, the majority charge (current) carriers are holes and the electrons are the minority charge carriers.
Where does the emitter and collector connect in PNP?
Emitter and collector are always on the two extremes. Therefore, in the case of PNP, the emitter and collector region connects to the P-type semiconductor and base to that with N-type. The construction can be understood by visualizing two diodes connected one after the other (see the above figure).