Protection Diode Ciruit Working and Its Application

In general, various electrical and electronic circuits can be built with numerous electrical and electronic components, that include resistors, diodes, capacitors, transistors, ICs (integrated circuits), Thyristors, transformers, etc. Right from the project design or in production diodes are mainly used in several applications. There are different types of diodes based on the specifications, characteristics, and applications such as a P-N junction diode, a Varactor, Zener, photosensitive, photodiode, and a protection diode, etc. For a better understanding of this concept, this article discusses an overview of what is a protection diode, protection diode circuit working and its applications.

What is is a Protection Diode?

A protection diode used in any circuit that allows the flow of current in the forward direction, because the current will not flow in the reverse direction. It protects the components which are responsive to the flow of current through them in the wrong direction.

Protection Diode
Protection Diode

Protection Diode Circuit

A protection diode used in a circuit is shown below. The following circuit is built with a protection diode to protect the circuit. For instance, the following project uses a protection diode that is connected in series with a light-emitting diode. An LED is pretty responsive to current in the reverse direction. It can only knob a certain amount of current in the incorrect direction. If sufficient reverse voltage drops across the LED then it will break down and let current to flow through it in the reverse direction, which can root the LED to be lastingly damaged.

Property of a Protection Diode
Property of a Protection Diode

The circuit below shows how a protection diode lets the flow of current in the forward direction and blocks the flow of current in the reverse direction. This provides to protect devices in a circuit that could be smashed from reverse current flow. Even though the following circuit provides protection through a diode, there is another way to use this protection diode in a circuit. The circuit below is a protection diode used in a circuit.

To keep a component safe in a circuit, a protection diode is normally located in reverse bias in parallel with the other component. Whenever a diode is positioned in parallel with the element you want protected reverse biased, if the flow of current through the circuit is in reverse, then the current flows through the diode, go around the motor. With huge amounts of current, some current may still pass through the motor, but it will be split between the diode and the motor. Therefore, all of the current will not flow through the motor, as would be the case if there was no diode present.

Property of a Protection Diode
Property of a Protection Diode

The entire circuit with the reverse-biased diode works better than the circuit before because, in the first arrangement, the diode consumes power. If the diode is a silicon diode, it usually takes about 0.7V of power. With this arrangement, the diode only consumes current when there is reverse current. Also, another cause to build it this way is the limits of a diode is reverse biased. In the first circuit with the reverse flow of current, the diode is connected in reverse bias. The flow of current will not to the peak reverse voltage of the diode. This voltage is the maximum voltage that a protection diode can endure to its cathode terminal.

Any voltage away from this will cause the diode to break down & conduct current. For instance, with a diode 1N4001, the peak reverse voltage can hold out is 50V. Thus, if the voltage surpasses 50V to the cathode fatal, it will break down and current will conduct. This is the control of the first protection diode circuit design. But, with the second design, there is no control, because the protection diode is forward biased with overturning current. So, it will never arrive at a breakpoint with this setup. Therefore, this arrangement with a diode in parallel reverse biased with the element to protect is better in design and a superior version of a protection diode circuit.

Applications of Protection Diode

Protection diodes are used with relays to protect integrated circuits and transistors from the brief high voltage generated when the relay coil is turned off.

Protection Diodes for Relay

The following circuit is the best application a protection diode where the diode is connected across the relay coil. In the following circuit, the diode is connected backward. So in general, normally it will not conduct. Conduction only happens when the relay coil is turned off since at this moment current seeks to continue running through the relay coil and it is safely diverted through the protection diode. Without this diode, there is no flow of current and the relay coil would produce a harmful high voltage ‘spike’ in its effort to keep the current flowing.

Application of a Protection Diode
Application of a Protection Diode

There are various types of protection diodes, the maximum current and the maximum reverse voltage of these diodes are

  • The diode IN4001 maximum current is 1A and the maximum reverse voltage is 50V
  • The diode IN4002 maximum current is 1A and the maximum reverse voltage is 100V
  • The diode IN4007 maximum current is 1A and the maximum reverse voltage is 1000V
  • The diode IN4001 maximum current is 3A and the maximum reverse voltage is 100V
  • The diode IN4008 maximum current is 3A and the maximum reverse voltage is 1000V

Therefore, this article discusses the protection diode circuit working and its applications.We hope that you have got a better understanding of this concept. Furthermore, any queries regarding this concept or electrical and electronics projects, please give your valuable suggestions by commenting in the comment section below. Here is a question for you, what is the main function of protection diode?

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