Table of Contents
- What are LED Chips?
- How do LED Chips for LED Strip Lights Work?
- Different Types of LED Chips
- LED Chip Sizes
- Which LED Chip is the Brightest?
- Qualities to Look for When Buying LED Chips
- How Manufacturers Test LED Chip Reliability
LED strip lights are a popular lighting solution due to their energy efficiency characteristics as an alternative to incandescent lighting. LED strip lights save you money in the long run, they’re environmentally friendly, and – above all – they can effectively illuminate your space. The LED chips are the heart of LED light strips; they are the components that convert electrical energy into the light that is produced and seen.
To understand how this technology works, follow along as we explain what it is, the science behind it, the various kinds, and the different aspects to consider when choosing the right lights for you. You can also learn about how LED strip lights are made.
What are LED Chips?
Light Emitting Diode (LED) chips are found in every LED light fixture because they serve as the core lighting component. The chip is a solid-state semiconductor device that converts electrical energy into light. This is an essential element of LED strip lights because of its role in determining light quality. Different LED chips are produced with various brightness, wavelengths, and voltage through a process called Metal-Organic Chemical Vapor Deposition (MOCVD), where layers of semiconductors are made to allow electricity flow.
How do LED Chips for LED Strip Lights Work?
For LED chips to work, an outside source of electricity is needed to run current through the chips. LED chips are a type of P-N junction diode. These are formed when a p-type silicon semiconductor material, where the hole is dominant, is combined with an n-type silicon semiconductor material, which mainly has electrons. The P-N junction combines the positive p side with the negative n side to give energy in the form of heat and light. When electricity is applied to the chip using wires, electrons are driven to the P-zone, which is then combined in the hole and generates energy in the form of a photon.
The material used in the P-N junction will determine the LED’s wavelength of light or color. Although LED chip technology doesn’t know how to produce white light directly, it generally has blue-colored light with a wavelength of 450-460 nanometers. Blue light conversion to white light energy in the chip happens in these three different processes:
A process known as phosphor down-conversion utilizes chemical powders called LED phosphors, which convert higher blue light energy to a lower light wavelength.
LED chips are given a voltage range to determine an LED bulb light output. The power content results in different light outputs since they control the bulb’s energy efficiency. Learn more about voltage drop for LED strip lights.
The LED chip determines the build light’s output and controls LED strip light brightness.
Different Types of LED Chips
Every chip comes with different benefits and usage. To better understand which LED strip lights to buy with the best chip for your convenience, we’ve listed the seven main kinds below with their defining attributes:
1. Dual In-line Package (DIP)
This is the traditional design of what people commonly think of as LED lights. It’s shaped like a bullet (≤5mm wide) with long contacts that extend outside its bullet form. This type of LED chip is broader and heavier compared to others.
2. Surface Mounted Diode (SMD)
This kind of LED chip can be integrated into commercial applications such as Linear LED Strip Lights or Downlights. Like its name suggests, it has a ceramic base and is mounted and soldered flat against a circuit board compared to a regular LED chip; SMD chips are much smaller, cost less, and have an improved beam angle.
Advantages over DIP LEDs include:
- Smaller and Slimmer
- Higher lumen output
- Improved heat dissipation
- Lower lumen depreciation
- Longer useful life
3. Chip on Board (COB)
These are high-powered multiple LED chips that are directly bonded to a printed circuit board (PCB) by the manufacturer to form a single module. The circuit board controls the thermal elements to prevent the bulb from overheating.
- Compactness due to the small size of the LED chips
- High intensity at close range
- High level of uniformity even at a working distance
- Better lifetime, stability, and reliability are achieved due to superior thermal performance
4. Multiple Chips on Board (MCOB)
This extends the COB technology package. Compared to numerous SMDs mounted together, MCOB LEDs appear more like lighting panels than individual fixtures. It has a low failure rate since there are more minor soldering points as soldering is unnecessary for this type of LED chip. MCOB is generally utilized in high bay light and floodlight applications. Its advantages may include producing more light sources in the same emitted area than a standard LED because of its multi-chip package. This results in a higher lumen output per square inch.
5. Multiple Chips and Cups on Board (MCCOB)
MCCOB refers to when numerous LED chips are placed in a cup that supports them. This technology is also generally applied in high bay fixtures and floodlights.
6. Flip-Chip (FC)
This is the opposite of the COB LED technology as it’s mounted upside down. It’s found to have reduced thermal resistance, a cost reduction advantage, and higher heat dissipation than traditional LED chip technology. This is more compact and brighter as well.
7. Smaller-Designed Light Beam Chips
These are otherwise known as Stereoscopic Chips on Board (SCOB) and have similar benefits to FC technology.
LED Chip Sizes
You might have run into multiple numbers on LED strip lights as you were looking for them. What do those numbers mean? Those numbers are not codes but physical sizes of the LED chips. The “SMD” before every number stands for Surface Mounted Diode, which means that the chip is attached directly to the strip without using wires. Its specifications include lumens, amp/wattage draw, and diode size. Below is a breakdown of each so you know what you’re buying.
- SMD 2835 is a mid to high-powered LED chip that is 2.8mm x 3.5mm in size (hence the 2835 name) with a surface area of 9.8mm², producing 25 lumens. It looks very much like SMD 3528, but it is thinner and made with a newer technology that renders it more energy efficient. This chip is, so far, only available for white LEDs.
- SMD 3528 is the most common chip size among other LED light strip chips. It is 3.5mm x 2.8mm in size (hence the 3528 name) and has a surface area of 9.8mm². It’s a low-powered LED that produces 6 to 8 lumens. Although SMD 3528 is gradually being substituted by SMD 2835, some manufacturers still have 3528 LEDs.
- SMD 5050, also known as “tri-chip,” has a 3-LED design that creates three times higher brightness than SMD 3528 at about 16 to 22 lumens per chip. It is also available in a “quad-chip” design. These chips are typically used for task lighting and cove lighting in homes and businesses. It measures 5.0mm x 5.0mm (hence the 5050 name) with a surface area of 25mm². It’s available in warm and cool whites, red, green, blue, amber single-color, and color-changing – either RGB or RGBW.
- SMD 5630 is smaller than the 5050 at 5.6mm x 3.0mm (hence the 5630 name) with a surface area of 16.8mm². Despite this, it has a greater light output of up to 50 lumens per chip. Appropriate applications for this chip size include hallway and stairway lighting, window and deck lighting, border, and trail lights. These are popular for commercial use, ideal for malls, theaters, clubs, and restaurants.
Which LED Chip is the Brightest?
The highest luminosity an LED chip can achieve is that of the SMD 5630 at 45-50 lumens per chip. Its great adaptability makes it high in quality, reliability, output, and value.
Qualities to Look for When Buying LED Chips
Brightness and Efficiency
For more focused and controlled lighting, especially if the LED light is to be used in larger areas, we recommend buying COB LED over other chips. This is because it uses reflectors and produces higher lumens with less energy use. For outdoor usage with sunlight exposure, DIP LED illuminates better than SMDs.
LEDs are known long for their energy efficiency and low maintenance, which results in lower costs over time. The better the quality, though, the higher the cost might be. However, it can also mean a longer lifespan if you don’t want frequent replacements with your lighting. DIPs tend to be the most expensive, while COB LEDs generally have a lower upfront cost than others.
The adjusting feature of LEDs is a popular trend (and rightfully so!) as it allows for more customization. Different color ranges such as RGB, RGBW, white light, blue light, and more can be illuminated by the sunlight. You can choose the device with the color(s) you want while still finding a great value (improved quality at a relatively low cost).
Longevity and Thermal Performance
More effective dissipation of the heat produced by the LED chips is what ultimately increases the longevity of the LED light strips. It is important to evaluate the different kinds of chips based on this aspect. For example, COBs are the kind that typically have a larger cooling area and better thermal resistance. However, SMDs have better heat dissipation (low optical decay) and a longer lifespan.
Size and Weight
Some LED chips take up more space and at the same time they often weigh more than others. DIP LEDs are generally larger and heavier than other chips, but their redeeming quality is that they are more durable and weather resistant.
How Manufacturers Test LED Chip Reliability
In the past, the luminous efficiency and brightness of LED technology was limited to only certain applications, such as indicator lights. Now, various improvements have been made, and its uses have expanded to a wide variety of applications, including signal lights, residential lighting purposes, decorative and accent lighting, full-color screens, and commercial and business purposes.
As the LED application range extends, the development of these fixtures continues to upgrade. The upgrade begins in its essential component – its chips. LED chips are designed to be long lasting and reliable. In every production, chips are tested, and the feedback is used to improve their quality and increase their reliability.
Theoretically, LED lights last for around 100,000 hours of usage. It might be challenging to test the level of reliability and device life if you try your LED chips using everyday rated stress. It’s suggested to make an objective assessment to gauge the LED chip’s light output.
As an example, take a random sample with 8 to 10 chips, made into 5 single lamps, a 30mA working current, a maintained room temperature (20-30̊ Fahrenheit) for environmental conditions, and a test period of 96 hours.
The durability test to increase electrical stress goes as follows. The working current 30mA is multiplied by the rated value. Take the random sample of 8 to 10 chips and package them into 5 single-lamp devices. Finally, run a 96-hour life test on them.
Life Test Bench
This test can perform up to 550 LED life tests simultaneously. It is comprised of a life test unit board, a stand, and special power supply equipment.
One way to run this test is by connecting the LEDs in a parallel fashion by conjoining the LEDs’ positive and negative ends. To get a consistent operating current, a steady forward voltage (Vf) is required, and the Vf should be the same for each LED. Vf for LEDs indicates the voltage required to achieve the desired current flow and turn the light on, which is contingent upon drawing the ideal current.
However, specific LED properties differ slightly in terms of their characteristics. When conducting the test, the same LEDs should be tested because differences might cause different operating currents due to the phenomenon of heat dissipation. LEDs with poor heat dissipation tend to rise in temperature more rapidly. The Vf declines when voltage is high, which causes the operational current to climb. Although these circumstances can be controlled using a series resistance current limiter, there are still downsides, such as a significant difference in operating current and forward voltage, which is not ideal because they need to be congruent.
The other way to run the life test bench is to connect the LEDs in a series, where the positive and negative ends of the LEDs are connected in a string. In most cases, the current limiting resistor R must be connected in series. If one LED is open (open circuit) in a single string, the 8 LED lights in that string will subsequently go out. The possibility of experiencing the open circuit is minimal, though. The series connection design for a constant current drive is typically best due to its simplicity, reliability, and cost-effectiveness.
Advantages of using life test bench’s design plan:
- Accurate, adjustable, and constant
- It can be opened and closed due to its microcomputer timing control capability
- LEDs with varying Vf can be used without having to make adjustments
- A low voltage power supply is used for safety
In conclusion, modern technology is evolving as goes on. LED light strips are becoming more advanced with more options available thanks to myriad improvements, notably in the increased sophistication of LED chip technology. Manufacturers are constantly innovating to produce LED chips that can be personalized to individual needs. LED chips need not be judged according to their size but the advancement in each device. Now that you know how an LED chip works, which kinds/sizes are available, and how to test them, we hope you feel more confident in your LED light strip selection process and overall understanding. Ultimately, look for the device that produces a brighter and better light output while using less energy.