The most difficult part about getting an LED display is its technical side. Learning about its functionality and the technology that allows LED screens to function is crucial. Answering questions like what is a diode and what it’s used for is necessary if you want to fully invest in LED displays. 

Many developments have been produced to create better LED displays that are capable of performing better and delivering high-end features that contribute to their functionality and effectiveness. To understand these developments, it is vital to learn the basics about diodes since they are responsible for the operation of these displays. 

Basic Definitions of a Diode

Learning more about LED displays will mean understanding their composition and looking into diodes. In this journey, the first step is to define what a diode is and how it can be used so that an LED screen can operate.

What is A Diode – A Diode

What Is a Diode?

Answering the question “What is a diode?” is the first step to this process of getting to know LED better. A diode is a straightforward semiconductor that serves as a button that turns the electricity on for the device. It allows electricity to flow one way while limiting the flow from the other way around. 

What is a diode in electronics? One simple answer is that it’s a rectifier. This means that it transforms AC (alternating current) into DC (direct current). Through their polarity (with anode and cathode), diodes can facilitate current flow only when the voltage is positive through either the anode or cathode. 

Two materials used in diodes are germanium and silicon. These semiconductor items help the diodes perform their functions successfully. They also protect circuits through voltage limitation, making it possible for the electric transmission to be successful. 

Diode Symbol To Know About

If you’re interested in what is a diode in electronics, you also need to be interested in its symbol. Identifying the diode symbol will make it easier for you to learn more about this semiconductor. An arrow symbol cut short by a vertical line on its head is the standard diode symbol as seen below.

What is A Diode - Symbols
What is A Diode – Symbols

The direction where the arrow symbol points may differ depending on the direction in which the current flows. The symbols show the two terminals of the diode, where the arrow represents the anode while the other end shows the cathode. This means that different symbols can crop up from this setup. 

Characteristics Of A Diode

Another vital detail you should know when answering the question of what is a diode is that the transmission of current has a direction. While it may only flow in one direction, the direction of the flow may differ depending on the type of diode involved. This bit of fact leads to the different characteristics you can identify on diodes, including the following:

  • Forward-biased – The anode has a more positive voltage compared to the cathode terminal. In this setup, the diode functions as a transmitter, allowing electric current to flow. There is also a noticeable decrease in voltage when the diode is forward-biased. Here are some of the features of this diode:
    • P-type material – Positive
    • N-type material – Negative
    • Potential energy – Positive
    • Silicon diodes – 690 mV
    • Germanium diodes – 300 mV
  • Reverse-biased – The cathode has a more positive voltage compared to the anode terminal. This happens when the diode restricts electrical flow and simply functions as an insulator. The voltage is completely dropped. Here are some of the features of this diode:
    • P-type material – Negative 
    • N-type material – Positive
    • Potential energy – Positive
    • Silicon diodes – -20μA
    • Germanium diodes – -50μA
  • Zero-biased – This is when the voltage of the diode is zero. 

Definition of Terms About Diode

To dig deeper to answer what is a diode, looking into some of the terms you’ll encounter in your study is necessary. Defining these terms connected to diodes will help you make the learning process easier and smoother. 

What Is a Diode Bridge?

What is A Diode - Diode Bridge
What is A Diode – Diode Bridge

When asked, what is a diode bridge, you should know enough to be able to answer. It is a module that serves as a connector between diodes. It is often used when you’re packaging four to six diodes in one module. In the end, it also acts as a rectifier for alternating current transforming into either pulsating or direct current. 

What Is a Diode Test?

Now, what is a diode test? It is a procedure where a tiny electric current is produced just enough to set a forward-biased diode to operate. A digital multimeter tester will help to check for this.  These are the readings you can expect from this test:

  • Voltage drop – 0.5 to 0.8 V
  • Resistance (Forward-biased) – 1000 to 10 ohms
  • Resistance (Reverse-biased) – OL or very high resistance

If the test shows that the diodes fail in the evaluation, these are the possible reasons:

  • It falls short
  • It allows electric flow in both directions
  • The current flow is halted 

Understanding Diode Operations

What is a diode in a circuit? It is a necessary component for the device to operate. It’s vital to have a basic understanding of how diodes work. This will help you appreciate the genius that makes up an LED screen

What Is a Diode and How Does It Work?

Manufacturers can easily answer the questions of what is a diode and how does it work but you should at least know the basics. For diodes, there are two ways in which they act depending on the type of polarization applied to them:

  • Direct polarization – capable of allowing electric flow
  • Reverse polarization – capable of restricting electric flow

These two behaviors play an important role in how the diodes function and where they are applied. 

Types of Diodes

What is A Diode - Types of Diode
What is A Diode – Types of Diode

More than just knowing what is a diode used for, you also need to look into some of the types of diodes used in devices today. Diodes vary in different aspects, including current capacity and configurations. There are also specific characteristics that set them apart from each other, along with the applications that are unique to them. These are the most common diodes used today. 

Light-emitting Diode or LED

Light-emitting diodes or LEDs are popular because of their integration into high-definition displays. This type of diode produces light when electricity passes by. The light-emitting diodes often generate colored lights, which are responsible for producing LED displays

Gunn Diode

This type of diode is associated with high-frequency electronics and has frequencies that can range from 10 GHz to 3 THz. Defining what is a diode of this type will naturally point you towards microwave oscillators. 

Laser Diode

This diode type also produces light similar to LED but is only more cohesive and affordable than other laser emitters. Its popular applications include printers, DVDs and CD drives, pointers, and even optical communications. 

Varicap Diode

Also known as a varactor diode, this type of diode uses reverse polarization, which basically means that it acts as a capacitor. Its capability heavily relies on the voltage of the current integrated into the diode. 

Zener Diode

The zener diode is considered one of the most common and useful diode types that ever existed. This is because the diode is capable of catering to a stable current, which is why it’s mostly applied in power supplies. It uses reverse polarization in its operations, making it possible to create a stable current reference. 

P-N Junction Diode

This diode type is commonly referred to as the rectifier diode. The diode consists of semiconductor layers made from P and N-type materials, which is how it got its name. It facilitates current flow in the forward direction and restricts the flow in the reverse direction.

Diode Applications To Look Into

What is A Diode - LED Diode
What is A Diode – LED Diode

Another aspect to fully answer the question “What is a diode?” is to consider all the applications where they can be used. Here are some of the most popular applications of a diode:

  • Current flow regulator – Facilitates and manages the flow of electricity in a circuit, enabling the current to flow in a single direction. 
  • Voltage rectifier – Acts as a power converter, where the diode can turn AC into DC whenever necessary. In diodes, both AC and DC can function if the right setup is used.
  • Reverse current protector – These diodes can be used as a protective element for devices with high electric sensitivity. With the diodes, the circuit is protected against voltage spiking and cases of short circuits. 
  • Negative remover – Diodes can be used to manipulate the AC wave and take out the negative component from it. This results in a more effective and efficient processing of signals for radios and similar systems. 


What is a diode? It is a powerful semiconductor capable of playing several roles like as a rectifier and as a circuit protector. When applied in LED displays, these diodes emit colorful lights that help make it possible to generate vibrant images on the screen. LEDs look like buttons that can be turned on or off, depending on what the needs are. When current hits the diodes, they produce colorful lights that result in the incredible videos you see on screens today.

Similar Posts