Identification of Diodes. LED, Transistor. IC. Resistor

The terminals through which an electric current passes are LED or light-emitting diodes. Two terminals that conduct both alternating current and direct current are resistors. A capacitor is a two-terminal device that stores some charge when a DC voltage is applied and does not allow direct current to flow through. A three-terminal device that has three legs is a transistor. 

Definition of a diode 

A semiconductor that contains two terminals is known as a diode. The diode with infinite resistance in the reverse direction and zero resistance in one direction is called an ideal diode. 

Diodes can not achieve infinite or zero resistance in the real world. Rather, diodes will have bare resistance in one direction, and in the reverse direction, diodes will have very high resistance. 

Semiconductor diode

Semiconductor diodes contain ‘P-N junction’ made from various doped semiconductor materials. These diodes are two-fold ended, non-linear electronic components, in which the terminal is connected to ‘p’ layer (+), referred to as the anode. The terminal connected to the ‘n’ layer is the cathode. 

The semiconductor diode is used because it provides electric current mainly from anode to cathode after forward-biasing the ‘P-N’ junction with the positive electric voltage. 

Semiconductor diode symbol

A diode is an arrowhead that points in the direction of recent formal flow from its anode (A) terminal to its cathode (K) terminal. 

Applications of semiconductor diode

• Voltage reference: This is a device that ideally generates a constant voltage irrespective of the temperature changes, power supply variations, and the passage of time.

• Mixing signals: Two signals are applied to a mixer that generates a new disparity of the original frequencies and signals at the sum of the original frequencies.

• Lighting: LED is a semiconductor when current flows through it, giving a source that radiates light.

• Laser diodes: These are similar to semiconductor LEDs. 

Explain LED 

The light is produced when the electric current between electrodes passes through the diode. Note light-emitting diodes are popularly known as LEDs.

Types of LED 

The following are the significant types of LED. let’s have a look – 

• Miniature LEDs
• High-Power LEDs
• Flash LED
• Bi and Tri-Colour LEDs
• Red Green Blue LEDs
• Alphanumeric LED
• Lighting LED

Introduction to Transistor 

In the year 1951, a scientist named William Shockley invented the transistor. The transistor which represented the junction transistor had the presence of P-N Junction Diode under reverse bias. However, it was not the first time a transistor came into existence. In 1947, J. Bardeen and W.H. Brattain were the first to invent something the world called a transistor. In this type of transistor, it was purely point-contact. 

The junction transistor by Shockley was the most popular. However, when new types of transistors came into existence, they started going by Bipolar Junction Transistor (BJT). Likewise, many other transistors are given specific names to differentiate them from the others. When the regular transistor is considered, we often link it to BJT.

Types of Transistor 

There are mainly two types of transistors. These include – 

Junction field-effect transistor

The junction field-effect transistor or JFET is one of the simplest transistors available. Due to the presence of majority charge carriers, the flow of current takes place. The junction field-effect transistor works in only one direction. It was first invented in the year 1953. 

The various types of a junction field-effect transistor are: 

• n-channel JFET 
• p-channel JFET 

The only difference between these two depends on the current flow and its causes if it is due to the electrons or the holes present.

Bipolar Junction Transistor

It is also known as BJT. It is further classified into two parts. These include – 

• N-P-N Transistor 

In this transistor type, the p-type carries the minority carriers of charge. At the same time, the n-type material has the majority carrier of charges at both ends. The base comprises p-type material, and the collector and emitter are composed of n-type semiconductor material.

• P-N-P Transistor

In this transistor type, the n-type carries the majority charge, and the p-type carries the minority charge. The two ends have the p-type material. There is a p-type material doped collector as well as an emitter.

Integrated Circuits (IC)

Integrated circuit (IC), also known as a microchip, is an assembly of electronic components fabricated as a single unit, in which miniaturised active devices (such as transistors and diodes) and passive devices (such as capacitors and resistors), as well as their interconnections, are built upon a thin semiconductor substrate (typically silicon).

Types of IC 

The integrated circuit can be classified into three types based on the nature of its input signals: analogue integrated circuits, digital integrated circuits, and mixed integrated circuits. Integrated circuits are used in almost all electric devices we see today. Mobile phones, laptops, televisions, and other electronic appliances are examples of these electronic appliances. 

Applications of Integrated circuits 

Integrated circuits come in a variety of shapes and sizes. The integrated circuit has a wide range of applications, including:

• Radiofrequency decoders and encoders
• Small-signal amplifiers
• Microwave amplifier
• Voltage regulators
• Video processors
• Memory devices
• Audio amplifiers
• Calculator chips
• Logic devices
• Wristwatches
• Juice makers
• Computers
• Televisions
• Radar

Resistor 

The resistor is referred to as a passive electrical component with two terminals used to regulate and limit the electric current flow in an electrical circuit. It is mainly used to limit or reduce the flow of current in any particular portion of the circuit. The resistor is made using copper wires wrapped around the ceramic rod. However, its outer part is coated with an insulator. The resistor’s SI unit is Ohm. 

Types of Resistors 

There are mainly two types of resistors. It includes a linear resistor and a non-linear resistor. 

With this, we end our study material on the Identification of Diodes. LED, Transistor. IC. Resistor. We studied diodes, LED, transistor, IC, and resistor in detail and explained their different types.

Conclusion

With this, we end our study material on the Identification of Diodes. LED, Transistor. IC. Resistor. We studied diodes, LED, transistor, IC, and resistor in detail and explained their different types. Semiconductor diodes are two-fold ended, non-linear electronic components. The terminal connected to the ‘p’ layer (+) is referred to as the anode, and that connected to the ‘n’ layer is referred to as the cathode. No external voltage is applied to the P-N junction diode in the zero bias.