1N5408 Diode Pinout and Specifications

1N5408 Diode Pinout and Specifications

Are you interested in finding out the pinout and specifications of a 1N5408 Diode? If so, then this blog post is perfect for you! Here we will explore the details of what is inside a 1N5408 Diode and how it works. This diode belongs to a set of silicon diodes that are known for their low voltage drop during forward conduction and fast response time. In addition, we will discuss why this diode is suitable for various electrical applications and which circuit elements should be used when making connections with these components. You’ll gain an understanding on how to effectively utilize this Pinout information with your setup as well as important safeguards when dealing with any type of electronic component. So let’s dive into uncovering the 1n5408 diode pinout in today’s blog post!

1N5408 Diode Explained

The 1N5408 diode is a commonly used general-purpose silicon rectifier. It has two pins, an anode and a cathode, and is capable of withstanding reverse voltage up to 1000V. For applications that require a high-current carrying capacity, the 1N5408 is an ideal solution.

Its uses range from AC/DC power supplies and battery charging equipment to motor control circuits.

When inserted into the circuit the 1N5408 conducts electric current from the anode to the cathode in one direction only. This makes it ideal for rectifying alternating current (AC) signals and blocking direct current (DC) signals in order to protect other components from damage or interference.

Overall, the 1N5408 diode is an extremely useful component in many circuit designs due to its versatility, small size and large current carrying capacity. It can be used in a wide variety of applications including AC/DC power supplies, battery charging equipment and motor control circuits among other things. Its ability to conduct electric current in one direction only also makes it invaluable in protecting components from damage or interference while allowing signals to pass through unhindered. Therefore, it will remain a popular choice for many circuit designers. [1]

1N5408 Diode Explained

1N5408 Pinout

The 1N5408 diode is a high power rectifier diode commonly used in power supplies. It has three pins, labeled Anode, Cathode and Gate. The anode of the diode is connected to the positive terminal of the supply voltage. The cathode is connected to ground or negative terminal while the gate pin remains unused.

The 1N5408 diode offers a maximum forward current rating of 3 amps, in addition to peak repetitive surge reverse voltage ratings as high as 1000 volts. Its average rectified current varies from manufacturer to manufacturer and can range between 1A & 3A. It also has a low reverse leakage current rating (1 microamp) at 25°C which allows it to be used as an isolation device in some applications.

Its maximum junction temperature is 150°C, allowing it to safely operate in higher than normal temperatures. [2]

1N5408 Features

  • Maximum forward current rating of 3A
  • Peak repetitive surge reverse voltage of 1000V
  • Average rectified current ratings of 1A to 3A depending on manufacturer
  • Low reverse leakage current (1 microamp) at 25°C
  • Maximum junction temperature of 150°C

These features make the 1N5408 a great choice for power supplies, especially those with high power requirements. It is also suitable for use as an isolation device in some applications due to its low reverse leakage current rating. The diode can be used in both AC and DC circuits, making it a versatile component for your electrical setup.

1N5408 CAD Models

The 1N5408 diode is a popularly-used three-terminal diode with an axial lead form factor. CAD models of the device are available via various online resources to assist circuit designers in creating and simulating their designs. These models provide detailed electrical characteristics, such as Forward Voltage drop (VF), Reverse Voltage rating (VR) and Maximum average rectifier current (IF(AV)).

The physical dimensions of the diode are also accurately represented in these CAD models, making it easier for engineers to integrate the device into their circuits without having to worry about size constraints. Furthermore, the accurate pinout information included within these CAD models ensures that engineers can easily connect the correct pins when assembling their circuits.

Ultimately, the availability of accurate CAD models for the 1N5408 diode is a major advantage for circuit designers, allowing them to quickly and accurately create their designs without having to worry about checking physical specifications or pinouts.

Overall, CAD models of the 1N5408 diode provide engineers with all of the necessary information they need to incorporate this device into their circuits. The accuracy of these models ensures that engineers can trust their designs and have full confidence in their ability to assemble reliable circuits. By taking advantage of these resources, engineers can save time and money while ensuring that their projects turn out just as planned. [3]

1N5408 CAD Models

1N5408 Replacement and Equivalent Diodes

The 1N5408 diode is a popular general-purpose diode that can be replaced with any of the following equivalent diodes: STTH100L, MUR1520, S1A-S12, FR107, and P6KE200. All of these diodes have similar pinouts and specifications as the 1N5408. Although the exact characteristics may vary slightly from one to another, they all serve similar purposes as rectifiers in voltage regulation and signal/waveform shaping applications.

The STTH100L diode is a high power rectifier with a maximum forward current rating of 100A and reverse breakdown voltage rating of 1000V. It has an average forward current of 10A and an average surge current up to 100A. The MUR1520 is a surface mount schottky rectifier with a maximum forward current rating of 15A and reverse voltage rating of 20V. It has an average forward current of 2A and a surge capability up to 15A.

The S1A-S12 diode is another popular general purpose diode with a maximum forward current rating of 1A and reverse voltage rating of 12V. It has an average forward current of 0.2A and a peak surge current up to 1A. The FR107 is also designed for general applications, with a maximum forward voltage rating of 1A and reverse breakdown voltage rating of 700V. It has an average forward current of 0.2A and a surge capability up to 1A.

Finally, the P6KE200 is a bidirectional transient voltage suppression diode with a maximum reverse breakdown voltage rating of 200V. It has an operating temperature range from -55C to 150C and can handle peak pulse power up to 600W. This makes it ideal for applications such as protecting sensitive electronic components from overvoltage conditions in automotive and industrial systems. [4]

Where to Use 1N5408 Diode

The 1N5408 diode is commonly used in a variety of electronics projects, including mains power switching, rectifying, overvoltage protection, and bridge circuits. It can be utilized as a flyback diode or free-wheeling diode for inductive loads to protect against voltage spikes. It can also be used in reverse polarity protection circuits to prevent damage from incorrect wiring. Additionally, the 1N5408 can be employed as part of a full-wave rectifier circuit for AC-to-DC conversion.

Due to its ability to handle high currents up to 3 A and withstand voltages up to 1000 V, it is an ideal choice for applications such as automotive circuitry and industrial equipment systems. Furthermore, the diode is relatively inexpensive and widely available, making it a popular choice for hobbyists, engineers, makers, and students.

In conclusion, the 1N5408 diode is able to handle high currents and withstand large voltages while requiring minimal external components. Its versatility and affordability make it suitable for applications such as automotive circuitry, industrial equipment systems, mains power switching, rectifying circuits, bridge circuits, overvoltage protection circuits, reverse polarity protection circuits and AC-to-DC conversion. As such, it is an excellent choice for hobbyists through to professional electrical engineers.

Where to Use 1N5408 Diode

How to Safely Long Run in a Circuit

The 1N5408 Diode is a popular general-purpose diode for a variety of applications. While its pinout and specifications are important considerations when integrating it into a circuit, the long-term operation of the device in that circuit must also be considered.
Ensuring safe long run operation with the 1N5408 Diode requires several steps:

  1. First, select an appropriate package size based on your intended application to ensure it meets current handling capacity requirements. Make sure the thermal resistance rating is adequate for your situation as well.
  2. Second, consider temperature coefficient; improper selection can result in poor performance over time due to deformation or even destruction of components. Additionally, if you plan to operate the 1N5408 Diode at elevated temperatures, look for a model that is temperature stabilized.
  3. Third, verify that the forward voltage rating is sufficient for your needs; if not, it may be necessary to use additional current-limiting components or cooling devices.
  4. Finally, when integrating the 1N5408 Diode into your circuit, take care not to exceed its maximum current ratings. Doing so can cause premature failure and may even result in dangerous thermal events due to overheating.

By following these steps carefully, you will ensure long run operation of the 1N5408 Diode in your circuit without any problems or risks associated with device failure. Furthermore, by selecting an appropriate package size, temperature coefficient and forward voltage rating you can ensure that your circuit will maintain its optimal performance over time.

1N5408 Applications

The 1N5408 diode can be used in a wide range of applications, such as rectification, freewheeling, power supply filtering, and reverse-voltage protection. It is also commonly used in circuits where fast switching action is required due to its low forward voltage drop and high current handling capability.

Additionally, the 1N5408 has a good surge capacity and can withstand transients of up to 600 volts with no damage or degradation. As such, it is suitable for use in automotive electronics and other rugged environments. Furthermore, this diode has an exceptionally low thermal resistance junction-to-case that allows for more efficient heat dissipation when mounted on a heatsink for some applications.

Overall, the 1N5408 diode is a versatile and reliable choice for many different types of circuits. Its low forward voltage drop, high current handling capabilities, good surge capacity, and thermal efficiency make it an ideal choice for designers who need fast switching action and robust protection against reverse voltages.

It is also a popular option in both industrial and consumer applications due to its cost-effectiveness and ease of use. Despite its relatively small size, the 1N5408 diode packs a lot of power into a tiny package that can provide reliable operation in even the most demanding applications. [5]

1N5408 Applications

1N5408 Package

The 1N5408 is available in two packages: DO-201 and DO-201AD. The DO-201 package has two leads and the DO-201AD has three leads. All of the pins on this diode are polarized, meaning that they must be connected in the correct orientation or else, they will not function properly.

The standard colors used for marking the polarity of a diode are red and white. The anode, which is generally marked with a red band, should always be connected to the positive terminal of the device while the cathode (marked with a white band) should go to ground or negative terminal.

While both parts of this diode have similar electrical characteristics, their mechanical characteristics differ. The DO-201 is designed to have a maximum of 500 volts while the DO-201AD can handle up to 1,000 volts and higher surge voltages.

The external package size of these two diodes are also different, with the DO-201 measuring in at 5.4mm x 4.5mm x 3.7mm and the DO-201AD coming out at 7.3mm X 6.2 mm X 3.6 mm respectively.

Both packages of this diode are suitable for use in a variety of applications, ranging from power supplies to rectifying AC signals for electronic circuits, making it an invaluable part of your electronics arsenal! [6]

1N5408 Package


What is the spec of 1N5408 diode?

The 1N5408 diode has a maximum peak reverse voltage (Vr) of 1000 volts and continuous forward current (If) of 3.0 amps. It also has an average rectified forward current rating of 2.6 amperes, with a non-repetitive peak surge current rating at 8.3 amperes. It is made from silicon material, with a power dissipation (Pd) of 10 watts and thermal resistance junction to ambient (RJA) of 150°C/W. The 1N5408 diode features an ultra-fast recovery time for high efficiency switch mode power supply applications.

What is equivalent to 1N5408 diode?

The most common equivalent diode to the 1N5408 is the STPS1000L. It has a peak reverse voltage of 1000 volts and can handle up to 8.3 amperes non-repetitive surge current. It features a low forward voltage drop, higher operating temperature range and fast recovery time for high efficiency switch mode power supply applications. Other alternatives include the UF5408, TIP127, D1S4 and BZT52C10.

What does N stand for in 1N5408 diode?

The “N” in 1N5408 stands for “Normal”, which is a type of rectifier diode.

Normal diodes are designed to have a forward voltage drop (Vf) between 0.7 and 1.2 volts, with the reverse leakage current (Irr) no greater than 500 μA at 25°C. The 1N5408 diode is a very popular normal diode due to its moderate cost and widely available pinout configuration. It has an average forward current rating of 3 A and can withstand up to 400 PIV peak inverse voltage (PIV). As such, it’s ideal for use in many low-voltage applications that require minimal noise, distortion, or power loss. Additionally, its low reverse leakage current makes it suitable for high-precision circuits. Its pinout consists of an anode and cathode terminal that are connected to a common ground symbol.

What is the difference between 1N4004 diode and 1N5408 diode?

The main difference between 1N4004 and 1N5408 diodes is their average forward current rating. The 1N4004 diode has an average forward current rating of only 1 A, while the 1N5408 diode can withstand up to 3 A. Another significant difference between these two diodes is their peak inverse voltage ratings. The PIV rating for the 1N4004 diode is 50 V, while the PIV rating for the 1N5408 diode is 400 V. Additionally, the reverse leakage currents of these two diodes differ as well; the 1N4004 has a maximum Irr of 30 μA at 25°C, whereas the 1N5408 has a maximum Irr of 500 μA at 25°C. Finally, the 1N4004 diode has a typical forward voltage drop (Vf) between 0.9 and 1.1 volts, while the 1N5408 diode has Vf between 0.7 and 1.2 volts.

Useful Video: WHAT IS DIODE, USE , WORKING, TYPES (IN4007,IN5408,6A4)


The 1N5408 Diode is a versatile component that can be used in a wide range of applications. Its features, such as its low turn-on voltage and high maximum reverse voltage make it suitable for many power electronic circuits. It can also be used for switching, rectification and protection purposes. With the correct pinout and specifications, this diode can easily be integrated into any design for reliable performance. In conclusion, the 1N5408 Diode provides reliable performance with great versatility to handle a variety of tasks. This makes it an ideal choice for your next project.

Thanks for reading! Feel free to leave any questions or comments below.


  1. https://www.apogeeweb.net/circuitry/1n5408-rectifier-diode.html
  2. https://www.componentsinfo.com/1n5408-diode-pinout-equivalent/
  3. http://www.el-component.com/diodes/1n5408
  4. https://www.futurlec.com/Diodes/1N5408pr.shtml
  5. https://components101.com/diodes/1n5408-power-diode-pinout-equivalents-datasheet
  6. https://www.utmel.com/components/1n5408-power-diode-pinout-price-datasheet?id=276