Which Diode Is Used In Soldering Irons?

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Diode features vast applications, and several devices use a diode for some vital reasons. When it comes to soldering iron, a diode is often used to aid in reducing input flow to a soldering iron heating element hence protecting it against overheating. This is a key feature that has to be fitted in every soldering iron to improve its functionality.

Which diode is used in soldering iron? Well, there are different types of diodes out there with some designed for solar panels, while others are used in a relay, among others. However, in this article, we shall be discussing the diode used in a soldering iron.

Which Diode Is Used In a Soldering Iron?

A PN Junction is the diode used for soldering iron; it helps in reducing the amount of power input to a soldering iron heating element. Usually, the diode is connected in series with a soldering iron heating element.

This is vital since when the heating element is connected directly to the source of power, it will end up overheating. However, with a diode in place and connected in series to the heating element, the power input will be maintained significantly.

The PN Junction in a soldering iron has been designed to act as a half-wave rectifier. The diode will conduct current during its positive half cycle hence allowing the heating element to have access to the power supply.

On the other hand, it will clock power supply to a soldering iron heating element during the diode negative half cycle. This means that the diode will be supplying power on and off continually to the soldering iron. As a result, it will protect it against overheating.

Usually, the PN Junction diode will reduce up to 50% of actual power input. Despite PN Junction being the most common diode in a soldering iron, some designs implement the use of LED (light-emitting diode) to help to facilitate the functionality of the iron. LED aids in reducing power, and it indicates whenever the soldering iron is on or off.

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What Is Pn Junction Diode, And Why Is It Commonly Used In Soldering Iron?

PN Junction diode is a semiconductor device that helps control the flow of electric current in a circuit. The diode is equipped with a positive side, as well as a negative side. Most of the PN Junction diode is designed from silicon. The silicone material allows this particular diode to operate at a higher temperature while protecting the heating element from overheating.

However, you should note that since the PN Junction diode features positive and negative sides, it does not mean that it is electrically charged. Despite having additional impurities, this diode remains electrically neutral.

How it works is often the main reason why PN Junction is commonly used in soldering iron. When current is flowing in one direction with the PN Junction diode, it is often referred to as forward bias. In forward bias, things tend to work smoothly as the positive hole moves towards the negative hole and vice versa. As a result, it keeps the current flowing.

However, when the current is flowing in the opposite direction with a PN Junction diode, it is often referred to as bias. During the bias flow of current, the PN Junction diode will create a barrier in the middle of a semiconductor hence blocking the movement of both the electrons and holes.

During this process, the flow of current is stopped. It is due to its unique control of the current that makes it best for use in a soldering iron. The on and off feature of the PN Junction diode helps in protecting the heating element of a soldering iron from overheating.

What Is A Light-Emitting Diode, And Why Is It Not Commonly Used In A Soldering Iron?

A light-emitting diode, commonly referred to as LED, is a diode that emits light while conducting. This diode operates on the phenomenon of electro-luminance; it is where a semiconductor material emits light once placed under an electrical field influence.

Some soldering iron companies prefer using LED over PN Junction diodes in their products. However, PN Junction still remains to be the most common diode used in a soldering iron. Usually, the primary difference between the two is that LEDs often emit light, unlike a PN Junction diode, which doesn’t.

LED is designed from Germanium arsenide, commonly known as Germanium phosphide. This property has the ability to emit light. In addition to that, LED uses an electrical circuit to help in affecting electrical current.

PN Junction is considered the best diode for use in a soldering iron since its semiconductors conduct in one direction. On the other hand, LED semiconductors tend to emit light once placed in an electrical field.

Since the PN Junction diode conducts in one direction, it has the ability to go on and off automatically hence protecting the heating element from overheating. However, LED relies on an electrical circuit to help with interfering with the electrical current.

In addition to that, LEDs tend to convert energy into light, unlike the PN Junction diode, which converts energy into heat. It is due to these significant differences that a PN Junction diode is commonly used in designing a soldering iron over the LED.

Final Thoughts

A light-emitting diode produces light when connected in forward bias (the electro-luminance), and they are best for use as an indicator. With an LED, you will be able to see when the soldering iron is on or off.

On the other hand, a PN Junction diode is ideal for safety purpose use, especially in current sensitive circuits. With a PN Junction diode, a soldering iron will be able to stop the flow of current in a reverse direction, allowing it to protect the heating elements against overheating.

A rectifier diode is also used in some soldering iron, and they have been designed to convert alternating current into a direct current by getting rid of the negative half present in an AC wave. As we conclude, we hope that this article has been of help when it comes to understanding the type of diode used in soldering iron. 

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