An investigation of transistor current in npn and pnp bipolar junction transistors

The p-type base is connected to the negative potential in NPN. As we know that electrons are the majority carrier in NPN transistors, so the process of switching takes place rapidly in it than in the PNP transistors. As transistors are three connection semiconductor devices.

An investigation of transistor current in npn and pnp bipolar junction transistors

At least it was for me. So let me tell you, in a simple way, how transistors work. I even made a video for you, just to make it clearer. The transistor is like an electronic switch.

It can turn a current on and off. A simple way you can think of it is to look at the transistor as a relay without any moving parts.

What is an NPN Transistor? (with pictures)

Download Basic Electronic Components [PDF] — a mini eBook with examples that will teach you how the basic components of electronics work.

Check out the video explanation I made on the transistor: There are different types of transistors. And it usually looks like this: It has three pins: Base bcollector c and emitter e. And it comes in two versions: The schematic symbol for the NPN looks like this: How transistors work The transistor works because of something called a semiconducting material.

In a standard NPN transistor, you need to apply a voltage of about 0. When you apply 0. In the example above you can see how transistors work. A 9V battery connects to an LED and a resistor.


But it connects through the transistor. This means that no current will flow in that part of the circuit until the transistor turns ON. To turn the transistor ON you need to apply 0.

Imagine you have a small 0. In a practical circuit you would use resistors to get the correct voltage from whatever voltage source you have When you apply the 0. This allows current to flow from the collector to the emitter. There is also a transistor called PNP which works in the opposite way.

The transistor is also what makes amplifiers work.

Degree Programmes Offered | School of Engineering

Thereby, the transistor can amplify a signal. Do you understand how transistors work? Post your comments and questions below! Then go check out the LDR circuit diagram and see if you can understand it.Bipolar Junction Transistors, or BJTs, offer higher trans-conductance than MOSFETS and don't require separate gate drivers.


A particular strength is that they are current amplifiers capable of very high current densities. In a bipolar transistor, a small current applied to a control lead (a wire) on the transistor, controls the flow of current through the other two leads on the transistor.

Transistors . Based on the principles above, bipolar transistors can be one of two types: NPN (a p-region sandwiched between two n-regions) or a PNP (the opposite of an NPN). The current and voltage polarities of an NPN transistor are opposite those of PNP and vice versa.

Complementary NPN-PNP Silicon Power Bipolar Transistors Typical Current Gain Bandwidth Product PNP NJWG NPN NJWG IC, COLLECTOR CURRENT (A) 0 10 20 30 40 50 60 1 10 f Tau, CURRENT BANDWIDTH PRODUCT (MHz) a transistor; average junction temperature and secondary breakdown. of transistors, a Bipolar Junction Transistor and a Field Effect Transistor.

Here, we will be looking at a Bipolar Junction Transistor, which also divided into two categories, PNP NPN PNP.

An investigation of transistor current in npn and pnp bipolar junction transistors

Bipolar Junction Transistor is a three terminals device with the Base, Emitter, and A transistor amplifier is a current control device. Chapter Goals • Explore the physical structure of bipolar transistor • Study terminal characteristics of BJT.

• Explore differences between npn and pnp transistors. • Develop the Transport Model for bipolar .

The NPN Transistor | BJT Transistor Tutorial