How to Test a SMD LED with a Multimeter

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So, you’re using an SMD LED in your project, and now you have questions. For one, do you have to buy special test equipment for this? Not at all. All you need is a multimeter, and you’ll be able to test whether your LED works.

Why is it tricky to do an SMD LED test using a multimeter?

So you think that by looking at the datasheet, you can work out how to test a SMD led with a multimeter? Think again, my friend! There are several issues that make this a tricky process. 

  1. SMD LEDs are tiny and difficult to work with (especially in terms of your vision and dexterity) 
  2. A multimeter is a complex instrument that contains several features that can make it difficult to test power with.

Looking into these issues, we can now understand how beginners felt. The process on how to test a SMD LED with a multimeter can really be tricky. They might have tried to test the led when they soldered it to the board, but the multimeter didn’t show a value. The reason why it didn’t work is that they didn’t know how to use a multimeter. Well, no worries – we have written the basic steps to follow to perfect the SMD LED test.

Testing the SMD LED with Multimeter

It’s a good idea to test the electrical properties of LEDs before you actually start working on a project. You can do this by taking a multimeter and measuring the resistance of the led, the forward voltage, and the maximum current draw with the led in a circuit. 

When testing an SMD led with a multimeter, do the following steps:  

  1. Prepare what you will need: a multimeter, an SMD LED, a solderless breadboard, wires, a soldering iron, and a solder. 
  2. Start by measuring the voltage between the negative and positive of your multimeter with the multimeter set to 20v. 
  3. Then put your SMD led into the solderless breadboard and connect it to a resistor. 
  4. Then connect a wire to the positive of your multimeter and another wire to the negative of your multimeter, then connect the other end of the wires to the resistor. 
  5. Now turn the multimeter to 20v and then touch each wire to the positive and the negative of the multimeter.

When you are testing an SMD LED with a multimeter, there are few important things to remember:

  • One of the main things is the fact that you need to find the right pins on the multimeter in order to test the SMD LED. 
  • If you don’t find the right pins, you might damage the SMD LED.
  • When it comes to testing SMD LEDs, there is a need for a low voltage DC power supply. Ideally, you want a power supply that is of a high quality and has a low dropout voltage. 
  • It is also essential to have a power supply that is not capable of producing a high voltage, which can damage the LED. 

Other devices used to test SMD LED:

Devices such as the LCT-3305 are designed specifically for testing SMD LEDs. Such a device is capable of producing a 3V or 5V DC output, and the output voltage has a low dropout voltage so that the LED is not damaged. The 3V or 5V output can be used to test a wide range of SMD LEDs, including low voltage LEDs.

Knowing More About SMD Led

SMD LED is short for surface-mounted device LED. This type of LED is used to light LCDs, touch panels, and backlit keypads. It is also known as chip or chip onboard LED since they are mounted on the PCB using a SMD process. The SMD LED is the most common type of surface-mounted LED, and it is the most commonly used type of LED in the electronics industry.

An SMD LED is composed of three parts: 

  1. The Die – The die is the part of the LED that emits light; it’s made of silicon and emits light efficiently.
  2. The Lens – The lens is a plastic cover that gives the LED its color.  
  3. The Lead Frame – The lead frame is the metal holder that holds the die and lens in place.

To get the most out of SMD, use NPN and PNP transistors. You will need to have a circuit diagram to show you where to put these components. In most cases, a breadboard and jumper wires are used to connect the circuit.

SMD LED Advantages

SMD LED lights have many advantages over the other LED lights, such as: 

  • Easier to use: SMD LED lights are easy to use and install, making them a good option if you are looking for a quick upgrade from a regular incandescent bulb. Also, SMD LED lights are compatible with regular E26 sockets as they use the same base as a typical incandescent bulb. 
  • No Heat: SMD LED lights don’t produce a lot of heat, so they don’t require a lot of cooling like halogen lights, and they are a better choice for your home or business if you have an HVAC system. 
  • Long Life: SMD LED lights to last a lot longer than incandescent lights, usually lasting

As you may know, SMD LEDs are the most commonly available types of LEDs and are used in a wide variety of consumer products, such as televisions, computers, and cell phones. SMD stands for a surface-mount device, which in this case means that the LED is mounted to a small circuit board rather than being soldered to a large circuit board, like the kind used for most other types of LEDs.  


SMD LEDs are usually extremely small and difficult to work with. It is very difficult to use a multimeter to test SMD LEDs due to the high voltage required by the multimeter to test the voltage of the LED. This can easily damage the LED. But with proper tools and knowledge, you can definitely run SMD LEDs without a problem.

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