Power Diode

Diodes play a significant role in power electronics circuits. These are uncontrolled rectifying devices. It acts as a switch to perform various functions such as switches in rectifiers, change reversal of capacitor and energy transfer between components, voltage isolation, energy feedback from the load to power Source.

• Diodes consist of semiconductor materials, either silicon or germanium.
• It is a two terminal semiconductor device, these two terminals are called the anode and cathode.
• It lets the electricity to flow only in one direction.
• Most diodes have painted line on one end showing the direction or flow. The negative side is normally white
• Current flow through diode only when positive voltage is applied to anode and negative voltage is connected to cathode
• If these voltages are reversed, then the current will not flow.

Applications of Power Diodes

• They act as shields for solar panels.
• They are used to protect loads from voltage spikes.
• They are used in voltage and converting it from AC to DC.
• They are used to allow an unidirectional flow of current in circuit.
• They differ by its power, and how much current it can handle.
• They act as an electronic check valve and convert alternating current into direct current (DC).

The vi characteristics of pn junction diode can easily be understood under the following three headings.

• Forward-Biased Diode
• Reverse-Biased Diode
• Zero Biased Diode OR Unbiased Diode

Forward-Biased Diode

In forward biasing semiconductor is connected to an external source when the p-type semiconductor is connected to the positive terminal of the source or battery and the negative terminal to the n-type, then this type of junction is said to be forward-biased. In forward bias, the direction of the built-in electric field near the junction and the applied electric field are opposite in direction. This means that the resultant electric field has a magnitude lesser than the built-in electric field due to this there is less resistivity and therefore depletion region is thinner. In silicon, at the voltage of 0.6 V, the resistance of the depletion region becomes completely negligible.

Reverse-Biased Diode

In reverse biasing, the n-type is connected to the positive terminal and the p-type is connected to the negative terminal of the battery. In this case, the applied electric field and the built-in electric field are in the same direction and the resultant electric field has a higher magnitude than the built-in electric field creating a more resistive, therefore depletion region is thicker. if the applied voltage becomes larger, then the depletion region becomes more resistive and thicker.

Zero Biased Diode OR Unbiased Diode

When there is no external source applied to semiconductors is known as an unbiased diode. the electric field is built up across the depletion layer between the p-type and the n-type material. this happens because of the unbalanced no. of electrons and holes due to doping. At room temperature, for a silicon diode, 0.7V is the barrier potential.

In electronic components, Power Semiconductor Devices are electronic devices that need an external power source to operate actively. Materials used to make semiconductor devices are neither excellent insulators nor conductors. They mainly manipulate, amplify, switch, or control the flow of electric current or voltage in a circuit. Power Semiconductor Devices, like diodes, transistors, thyristors, and sensors require power to do their job. A circuit is an interconnection of components. These components are capable of performing active functions like amplification, rectification, and switching they are called Power Semiconductor Devices.

In this article, we will be going through Semiconductor Devices Which are mainly divided into Diodes, Thyristors and Transistors. Semiconductor Devices are Classified into Two-Terminals, Three-Terminals and Four-Terminals Devices, We will go in-depth about these Devices. We will go through working of diodes, Thyristors, Transistors and Look at Its vi characteristics, At last we will conclude our Article with Advantages, Disadvantages, Applications, and Some FAQs.