LED Bulb Number Meaning

LED Bulb Number Meaning

by Frank K on August 02, 2023 Categories: News
When you get LED bulbs, numbers like 2835, 3528, 5050, and 7545 are commonly found in the description. Have you ever wondered the LED bulb number meaning?
The numbers 2835, 3528, 5050, and 7545 are commonly used to describe the dimensions of surface-mount device (SMD) LEDs. Each number represents the dimensions of the LED package in metric units (in this case, in tenths of a millimeter). These numbers are widely used to classify and differentiate SMD LEDs based on their sizes. Here is the breakdown of the meaning of the numbers, along with a clarification on CSP vs SMD:

2835: This number represents an SMD LED package with dimensions of 2.8mm x 3.5mm. The "28" stands for 2.8mm (width), and the "35" stands for 3.5mm (length). 2835 LEDs are commonly used in various applications, including LED strips, displays, and general lighting.
3528: This number indicates an SMD LED package with dimensions of 3.5mm x 2.8mm. The "35" represents 3.5mm (width), and the "28" stands for 2.8mm (length). Like 2835 LEDs, 3528 LEDs are also widely used in LED strips, backlighting, and other lighting applications.
5050 /7545: The number 5050 corresponds to an SMD LED package with dimensions of 5.0mm x 5.0mm. Both digits "50" indicate that the LED is a square with sides measuring 5.0mm each. 5050 LEDs are popular for their high brightness and are often used in applications where strong illumination is desired. Automotive lighting, decorative lighting, and signage generally use 5050 LEDs. Our DAMA H-Series LED bulbs (DAMA Kanji Lux Vision) use the highest Flip LED 7545 SMD chips. By using 7545 LED chips, DAMA creates a greater hotspot and throws a longer distance.
It's important to note that these numbers only refer to the package dimensions and not the electrical characteristics or color of the LED. When choosing an SMD LED for a specific application, it's essential to consider the required specifications such as forward voltage, forward current, color temperature, color rendering index, and viewing angle, which may vary between different LED models.

Another popular, and seems to gaining popularity is the CSP LEDs.
CSP LED stands for "Chip Scale Package." Unlike traditional SMD LEDs that have a separate plastic package, CSP LEDs have the LED chip directly mounted onto a substrate, resulting in a smaller form factor and improved thermal performance. A simple way to compare the CSP vs. SMD LEDs is if SMD LEDs are "wired" to the LED bulb body, CSP LEDs are "glued" directly to the body. One of the benefits is that CSP LEDs are slimmer than SMD LEDs. Like SMD, the CSP LED numbers typically refer to the dimensions of the LED chip itself.

For example, CSP LED numbers like "1313," "1818," or "2525." These numbers represent the dimensions of the LED chip in tenths of a millimeter. The first two digits indicate the width of the LED chip, while the last two digits represent the length of the LED chip.
As explained for the SMD chips, the same applies for the CSP chips:
  • 1313: LED chip is 1.3mm x 1.3mm in size.
  • 1818: LED chip is 1.8mm x 1.8mm in size.
  • 2525: LED chip is 2.5mm x 2.5mm in size.
  • 3570: LED chip is 3.5mm x 7.0mm in size.
As we mentioned previously, CSP LEDs are known for their compact size, high efficiency, and excellent thermal management, making them suitable for various lighting applications, including automotive headlights, general lighting, and backlighting. Our DAMA D1S, D3S, D8S, and our most popular D5S LED bulb use the 3570 LED chip for the brightest and whitest light output possible.