All Types of Diode Symbol and Diagrams
Here in this article, we are going to see all types of Diode Symbols. A diode is an electronic semiconductor device that acts as a switch for electric current. Generally, a diode allows the flow of current in one direction only without any restriction. Also, it allows the flow of current in opposite directions with some conditions. Knowing the symbol of diode is very important as it helps to understand electronics circuits or wiring diagrams that consist of diodes.
A diode is a two-terminal device named Anode and Cathode. The polarity of the diode is very important when used in electrical or electronic circuits.
The diode is an active device because it cannot work without an external voltage. An external power supply or biasing must be applied to the diode to work.
The different types of Diode are,
- PN Junction Diode
- Zener Diode
- Schottky Diode
- Shockley Diode
- Avalanche Diode
- Constant Current Diode
- Tunnel Diode
- Varactor Diode
- Step Recovery Diode
- PIN Diode
- Gunn Diode
- Laser Diode
- Light Emitting Diode(LED)
Read Also: All Types of Capacitor Symbol and Diagram
PN Junction Diode Symbol
PN Junction diode is the simplest diode among others. It is a two-terminal device. In normal conditions, it allows the flow of current in one direction only. The main application of the PN Junction Diode is AC to DC converter or Rectifier Circuit. Here you can see the symbol of PN Junction Diode.
Zener Diode Symbol
Zener Diode also almost does the same work as a PN Junction diode. It also allows the flow of current in one direction only. Just the difference is, it allows the flow of current in the reverse direction when its terminal voltage crosses the Zener voltage. But reverse current flow does not damage the diode. Here, you can see the symbol of the Zener Diode.
Schottky Diode Symbol
Schottky Diode is also known as a hot-carrier diode or hot barrier diode. Schottky diode is formed by the junction of a semiconductor with a metal. The advantages of a Schottky diode over a normal diode are, it has a very low forward voltage drop, very fast switching speed. Here, you can see the symbol of the Schottky diode.
Shockley Diode Symbol
It is a PNPN layer diode. Its construction is almost the same as a thyristor without the gate terminal. Shockley has two PN Junctions. Also, it may have multiple PN Junctions. Until the applied voltage crosses the triggered voltage it does not allow the flow of current. Once the applied voltage crosses the triggered voltage, its resistance decrease to low and current start flow. Here, you can see the symbol of Shockley Diode.
Avalanche Diode Symbol
Avalanche Diodes are those which work in avalanche breakdown mode without damaging themselves. In general, it does not allow current, but when the voltage across it crosses the breakdown voltage it starts conducting current. Here, you can see the symbol of Avalanche Diode.
Constant Current Diode Symbol
The constant current diode is also known as the current limiting diode or current regulating diode. The main function of this diode is to limit the flow of current through it under a certain value. Here, you can see the symbol of the constant current diode.
Tunnel Diode Symbol
The tunnel diode is also known as Esaki Diode. It is a semiconductor device that has effective negative resistance due to the quantum effect. Tunnel Diode is a heavily doped PN Junction Diode. Here, you can see the symbol of the Tunnel Diode.
Varactor Diode Symbol
Varactor Diode is a voltage-dependent semiconductor device. It always works in reverse bias conditions. The main characteristic of the varactor diode is, its internal capacitance varies with the varying of reverse voltage. It is also known as Varicap diode or varying capacitor diode. Here, you can see the symbol of varactor diode.
Step Recovery Diode Symbol
Step Recovery Diode is also known as a snap-off diode or charge storage diode. It is a specially designed for extremely short pulse signal. The doping density of the step recovery diode is extremely low. Here, you can see the symbol of the step recovery diode.
PIN Diode Symbol
A PIN Diode is made up by inserting an undoped intrinsic semiconductor material between the P-type semiconductor and N-type semiconductor regions. So, it has an extra layer between the P and N Junctions. This differs the PIN diode from a regular diode. Here, you can see the symbol of the PIN Diode.
Gunn Diode Symbol
Gunn diode is an electronic semiconductor device made up of only N-type semiconductor material. There is no P-type semiconductor material in the Gunn diode. Gunn Diodes are mainly used to create microwave signals. Gunn diode also has negative resistance properties. Here, you can see the symbol of Gunn Diode.
Light Emitting Diode(LED) Symbol
A light-emitting diode or LED is a special type of diode that emits light when connected to a power supply in the forward bias. In reverse bias, it cannot work or emit light. LED is made up of a special type of semiconductor material such as Aluminium indium gallium phosphide(AlInGiP). Here, you can see the symbol of LED.
Laser Diode Symbol
A laser Diode is also a semiconductor device almost similar to a light-emitting diode. It emits coherent light from its PN junction. The Laser Diode uses the process of "Light Amplification by Stimulated Emission of Radiation". Here, you can see the symbol of Laser Diode.
All Types of Diode Symbol and Diagrams
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June 28, 2021
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