COB Lights: What are Chip On Board (COB) LED Lights?

COB Lights: What are Chip On Board (COB) LED Lights?

When it comes to growing marijuana plants indoors you need to make sure that you are providing them with the best possible lighting. This is because under natural conditions outdoors plants get access to the natural light of the sun which is the best for their growth. However, indoor growers need to artificially recreate this kind of a light. This is done with the help of grow lights, which carry lights of different wavelengths that combine to form an output which is very similar to natural sunlight. Plants need different kinds of lighting during different stages of their growth cycle and grow lights ensure that they are getting them. One such kind of a grow light are COB lights – Chip On Board LED lights, which we shall be taking a detailed look at!

Before we get into the details of COB lighting, we will talk about why lighting is important for plants, and then look at the different kinds of lighting options that are available for indoor growers. Post that, we take a closer look at Chip On Board lights, and the difference between COB lights vs SMD LED grow lights. Both of these are essentially LED lights but are different in performance as well as the way they are built. 

We shall look at the pros and cons of COB LED lights, run through a quick buyer’s guide for COB lighting, and then look at the three best COB LED lights in the markets before we conclude. Let us first begin by addressing the basics:

Why Do Plants Need Lights?

Light is one of the most important things for a plant to grow properly. Plants need lights for a number of different things. First off, the biggest purpose that light serves is that it gets converted into energy via the process of photosynthesis. Under normal circumstances, plants absorb lights from the sun for this purpose. Indoor gardeners make use of ‘grow lights’ for it. Light also helps with a number of other functions such as breaking down of sugars, development of resins, increasing the foliage on the plants, ensuring denser and well-spread roots, as well as helps determine the flavour and smell of the plant among other things. 

Sunlight is needed at different phases of the plant’s growth cycle – for instance, the process of the plant entering from the pre-flowering stage to the flowering stage gets triggered when the sunlight hours reduce. While naturally it happens based on the seasons, but when you grow it indoors you can reduce the time the grow light is switched on to trigger flowering. Plants also need different kinds of light at different phases – blue lighting (cool spectrum) is needed during the vegetative phase of growth and warm red lighting is needed during the flowering phase. 

When growing indoors, grow lights are used. These lights are highly beneficial for growers because these lights can increase or decrease in brightness, the colors of these lights can be changed, the distance from where the light falls to the plants can also be tweaked based on the needs of the growers. You can create an ideal and ‘perfect scenario’ for your plants which would actually be better than what they would get when they get natural light from the sun. Sunlight can vary based on the weather, season, or even your geographic location – but grow lights are always going to provide you results under ‘ideal conditions’ because you are in complete control here.

Different Kinds of Grow Lights:

Let us now take a closer look at the different kinds of grow lights that are available in the markets for the growers to use in their grow tents/grow rooms:

1. High-Intensity Discharge Grow Lights

These are very bright lights but need to be changed during different stages of the plant’s growth cycle:

  • High-Pressure Sodium Grow Lights:

HPS grow lights emit warm red light and light up when an electric arc is passed through sodium vapor. These lights are great for the flowering stage of plants and are particularly beneficial when it comes to growing marijuana. HPS grow lights also tend to emit a lot of heat and disposing them is quite a task because of the chemical inside them. The light is to be used when the plant enters the pre-flowering phase. Using these grow lights will help the growers get bigger and better blooming flowers. 

  • Metal Halides:

Metal Halides are the exact opposite of what HPS grow lights are. These offer lighting in the cool blue spectrum which is great for the plants during the vegetative phase of their growth. These grow lights function on the basis of an electric arc being passed through mercury vapor. They help the marijuana plant get leafier and greener, and help the foliage develop properly. 

2. Fluorescent Grow Lights

Commonly referred to as CFL lights, these grow lights are beneficial for growers who want to use a source of light which does not emit too much heat but is very bright. However, the spectrum is quite limited when compared to HPS lights or LED lights because these are almost exclusively white or warm white in color. The white lights are used during the vegetative phase and the warm white lights come into effect during the flowering stage.

3. LED Grow Lights

These are the latest and the most advanced type of grow lights which a large number of growers prefer. The best thing about LED lights is that they consume the least energy while giving the most output. These lights also do not emit a lot of heat. Another great thing about using LED lights is that they come with individual diodes so if one of the connectors goes bad the light will still function unlike HPS/MH/CFL lights which go bad very quickly. The life span of an average LED grow light is about 50,000 hours and some premium ones can last you for over 100,000 hours. 

  • SMD LED Lights

SMD lights (Surface Mounted Device) are the standard LED lights. Here, the diodes are placed on chips in groups of up to 3 diodes per chip and each diode has its own set of connectors. LED lights can have hundreds of such chips based on the wattage that they provide.

  • COB LED Lights

COB LED lights are an improvement over SMD lights as they support the use of multiple diodes on a chip – a minimum of 9 with no upper limit. Furthermore instead of each diode having its own set of connectors there are only two connectors in COB bulbs. This makes them much brighter as well as the circuit becomes much simpler. 

What are COB Lights?

Chip On Board LED lights, commonly referred to as COB LEDs or COB Lights are a popular type of lighting solution that is used by the growers to light up their grow rooms or grow tents. While standard Surface Mounted Device (SMD) LED lights make use of a maximum of three diodes per chip, the number rises manifold when you compare it with a COB light, where a minimum of 9 diodes are placed together. In each diode of the SMD chip, you will find individual diodes having individual contact points which leads to some chips having up to 6 contacts! In case of a COB light, there is only one circuit and two contacts, no matter how many diodes are present!

Since COB lights have a much higher number of diodes in them, they are considerably brighter compared to standard SMD lights. However there’s one drawback to having a simpler contact and circuit system – this is that it leads to these lights not being able to change their colors and are used only where single-color is required. When it comes to growing plants, many modern-day grow lights come with one or two COB lights surrounded by SMD lights around it. COB LEDs also offer the growers with a much better lumen per watt ratio when you compare them with SMD lights. These lights are also very useful in places such as the bulb of a camera. 

Some people prefer to get their own set of DIY COB lighting. These growers like to get their own bulb, reflector, holder, heat sink, drivers and other equipment and assemble it all together to ensure that their COB light makes use of the best parts available in the markets. However, this is something that only advanced growers do. Most beginners and novice growers would prefer to use standard COB LED lights which are available on Amazon. Most of these lights make use of a combination of COB and SMD chips to provide an enhanced lighting experience for your plants. 

3 Best COB LED Lights For Growing Marijuana

Image Product Rating Price
1800 Watt X6 Cob Led Grow Light Full Spectrum Led Plant Light 1800 Watt X6 Cob Led Grow Light Full Spectrum Led Plant Light

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Phlizon CREE COB 3000W LED Plant Grow Light Phlizon CREE COB 3000W LED Plant Grow Light

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BESTVA Reflector-Series 600W COB LED Grow Light BESTVA Reflector-Series 600W COB LED Grow Light

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Here are the three best options that are available for growers who are looking forward to buying this kind of a lighting setup:

1. 1800 Watt X6 Cob Led Grow Light Full Spectrum Led Plant Light

1800 Watt X6 Cob Led Grow Light

1800 Watt X6 Cob Led Grow Light


  • Offers a wattage of 1800W
  • Full-spectrum light that suits all the different stages of the plant’s growth cycle
  • Supports daisy chaining

There are 6 COB lights attached to this grow light, which ensure that your plants are getting a really bright source of light. The grow light offers the plants with a full-spectrum light, which means it includes the red, blue, white wavelengths as well as UV and IR lights which are helpful for the overall development of the plants across different phases. The light offers you with an output of 1800W while consuming only 300W, which is really energy efficient when compared to HPS or MH grow lights. 

To ensure that this grow light remains cool at all points of time, three fans have been attached to the back which make sure that all the heat is dissipated off and does not damage the product or the plants. There are multiple heat vents on the sides to aid this as well. This grow light also supports daisy-chaining, which means that growers can hook in multiple grow lights on to each other instead of plugging each of them into a power source on the wall. Besides all this, another great advantage that growers get is that of a really long, 3 year warranty period along with a 90-day money-back guarantee. 

Check Price & Reviews on Amazon

2. Phlizon CREE COB 3000W LED Plant Grow Light Full Spectrum Indoor Plants Light

Phlizon CREE COB 3000W LED Plant Grow Light

Phlizon CREE COB 3000W LED Plant Grow Light


  • Very powerful and bright 3000W LED light using CREE COB LEDs
  • Full-spectrum lighting helps plants grow across all stages
  • Covers area of 4×4 ft

This grow light from Phlizon is one of the best options for growers who are looking for the perfect grow light for a 4×4 grow tent. With a massive 3000W output, this is one of the brightest grow lights that you could find in the markets and will do wonders for your plants. There are 6 COB lights along with 144 pieces of regular SMD diodes too. The full spectrum lighting helps your plants power through the different stages of growth all the way from seedling to harvest without much of a hassle!

While the output that you get from this grow light is that of 3000W, it actually consumes only about 600W from the power socket, which is one of the biggest plus points about this grow light, making it much more energy-efficient when compared to HPS/MH lights. The coverage is also decent. In addition to all this, there are six fans on the back which ensure that all the heat gets dissipated properly. There are two switches on the back to control between the VEG and BLOOM mode of lighting – and there are a number of vents on the sides for the heat to escape. Lastly, this grow light offers you a 2 year warranty period as well. 

Check Price & Reviews on Amazon

3. BESTVA Reflector-Series 600W COB LED Grow Light Full Spectrum Grow Lamp

BESTVA Reflector-Series 600W COB LED Grow Light

BESTVA Reflector-Series 600W COB LED Grow Light


  • Well established brand name
  • Quite affordable
  • 600W lighting with separate switches for VEG and BLOOM mode

While the two above are high-output lights with a bright lighting, they are quite an expensive purchase for many buyers. This grow light from Bestva, however, is a much more affordable option for growers, priced in at under $70. The light offers 600W of wattage – and claims to offer 30% higher PAR values than any other competing brand. There are separate switches for the VEG and BLOOM mode on this grow light, which make it easier for the growers to ensure the right type of light is reaching the plants during different stages of their growth. Marijuana plants require red lights during flowering and blue lights during the vegetative phase. 

When hung from a 24” height, this grow light can cover 2×2.2 ft of area, which is quite impressive. There’s a 5mm radiator inside the grow light which helps dissipate the heat, along with the four-fan set up in the back. You get a full-spectrum lighting here along with IR and UV lights, which helps your plants get the best possible lighting and an all-round growth. This is a great grow light for personal scale growers who do not need to cover a large area. Lastly, you get a 3 year warranty period covering this grow light along with a 90-day money-back guarantee – making this one of the best COB LED grow lights out there!

Check Price & Reviews on Amazon

Pros and Cons of COB LED Lights

Now that you know what Chip On Board lights are all about, here’s a quick look at the pros and cons of using such a lighting system:


  • Thanks to their simpler design and the ability to allow multiple diodes on one chip, they can be made smaller in size than standards LED grow lights.
  • These lights are among the brightest when it comes to grow lights because of the concentration of diodes.
  • The circuits of these grow lights are quite simple in comparison to other forms of grow lights (especially when compared to SMDs)


  • These grow lights cannot produce RGB color in the way SMDs can
  • Simpler circuits mean there’s a chance that if something goes wrong a large chunk of the light goes bad at once

COB LED Lights vs SMD LED Lights

Here’s a quick and detailed look at the difference between COB LEDs and SMD LEDs:

  • Number of Diodes Per Chip

In case of SMD LED grow lights, you can have as many as three diodes per chip at the most. However, in case of COB lighting, you can make use of a much higher number of diodes – starting with a minimum of 9 per chip and having no upper limit. 

  • Brightness

Because you can have a much larger number of diodes on a chip, COB lights tend to be much brighter than SMD LED lights. 

  • Circuit Layout

In case of SMDs, each of the diodes carries their own connector leading to up to 6 connectors per chip. However, in case of COB lights, there are only two connectors to the entire bunch – even if there might be a hundred diodes in the chip, only two connectors will be included. 

  • Colors

This is the one department where SMDs score above COBs. SMD LED grow lights can produce the RGB colors meaning that they can provide a much better range of colors which are more suitable for the growth of plants than COB LED grow lights. This is why most grow lights featuring COB lights also come with a number of SMD LED grow lights around it.

Frequently Asked Questions (FAQs) About Chip On Board Lights

Here are the answers to some of the most common and frequently asked questions about these kinds of lights that we get from our readers. We hope that going through these answers will resolve some of your queries and doubts as well! 

1. Are these lights legal to grow weed?

These lights are legal to grow all kinds of plants as long as the plants are legal to be grown. In many areas you cannot grow certain kinds of plants in your home without approvals. This is particularly about marijuana/cannabis plants which cannot be grown without prior permissions – and even these permissions can be quite limiting in nature up to a certain number of plants. 

2. Where can I buy COB lights from?

COB lights are pretty common and can be found at any super speciality store where you get gardening supplies. However, for the widest range, you might want to take a look at the Amazon store as that is where you can get the biggest collection of COB lights to suit all your needs! 

3. SMD vs COB Lights – which is better?

To be honest you’ll probably need a combination of COB + SMD lights to get the most out of your plants. In isolation both of them are good enough but SMDs get an edge because they can produce more colors while COBs have an advantage in terms of brightness, simplicity of the circuit design and heat dissipation!


We hope that by this point in the article you are well versed with everything that you need to know about COB LED lights. Chip On Board systems have been around since quite some time now and growers have begun to appreciate their value in indoor gardening. Marijuana growers can benefit a lot from using these bright lights. COB lights have a number of benefits but the one drawback of not being able to produce colors properly is one which continues to hold them back from the mainstream. Nonetheless, it is expected that in the years to follow, these lights are going to lead the way towards the future of gardening! Till then…

…Happy Growing! 🙂


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