COB LED strips

COB LED strips are a completely new variant of LED strips. COB stands for Chip-On-Board and this process was previously known for high-power LED modules.

With COB, the phosphor that produces the white light in LEDs is not applied directly to the individual LED chips, but a large array of LED chips is coated with a phosphor layer as a whole. What sounds very technical has a very decisive advantage in the application: you no longer see any LED dots! And none really means NONE, because the entire phosphor shines as a continuous band.

This is of course a decisive advantage for all applications where otherwise visible individual LEDs are a nuisance. Be it in a narrow aluminium LED profile where individual LED points would otherwise still be visible, or in a suspended linear luminaire, or even in indirect lighting where the distances are very short.

COB LED strips are very similar in structure to normal LED strips and can therefore be used in exactly the same way. The only difference is the application of the phosphor. With COB, it is applied as a whole over all LEDs and thus forms the continuous homogeneous light band. Everything else is basically the same. For example, the closely spaced LEDs sit on a flexible carrier strip that has double-sided adhesive tape at the bottom for easy mounting.

The light colour of COB LED strips

COB LED strips are available in all common colour temperatures from warm white to neutral white to cool white and in excellent colour quality CRI>90.The efficiency of COB LED strips is also very high. Many variants achieve around 100 lm/W and thus generate around 1,400 lumens per metre with a power consumption of 14 watts/m. This is even sufficient for indirect lighting. Even for indirect lighting – i.e. reflected via the ceiling – this is still enough luminous intensity to illuminate a medium-sized room sufficiently brightly. COB LED strips are therefore not only suitable for accent applications, but can do a lot more.

CCT & RGB COB LED strips

In the meantime, there are not only pure white COB LED ribbons, but also those with adjustable colour temperature and RGB variants for colour effects.

CCT COB LED strips do not differ externally from normal, pure white COB LED strips, but there are 2 different rows of LEDs under the COB layer that can be controlled separately, as is usual with CCT LED strips. In this way, an adjustable colour temperature can be realised.
The colour temperature can be changed within a range of 2,700K – 6,000K. All relevant white tones from warm white to neutral white to cool white can be set.

RGB COB LED strips, on the other hand, work completely without a phosphor layer. Here too, however, the LEDs are so closely arranged and installed under a slightly milky silicone layer that a completely continuous, homogeneous light band is created. The LEDs are installed in 3 rows of red, green and blue. Nevertheless, the light band itself is only a few millimetres wide and the entire band only 12mm. Tiny LED designs make this possible.

Advantages of COB LED strips

The following is a summary of the advantages of COB technology compared to normal LED strips

  • No individual LEDs visible
  • Homogeneous continuous row
  • Very flat, narrow aluminium profiles can be used
  • Simple installation and mounting (compared COB to Neonflex)
  • High efficiency and luminosity

Durability of COB LED strips

The basic technical process for COB LED strips is no different from that for normal LED strips. The light from blue LED chips is unconverted into white light via a specifically applied phosphor layer. Whereas in normal LED strips the phosphor sits directly on the LED chips, in COB strips it is drawn globally in a long line over all the LEDs.

Of course, there are certain signs of ageing with every phosphor, but these are negligible – provided the LEDs are mounted properly (keyword: aluminium profile). The phosphor remains stable for an extremely long time (many years) and you will not notice any visible change in light colour or brightness. Since with COB the phosphor is somewhat further away from the LED chip, and thus from the heat source, it can possibly even be assumed that the service life is slightly improved.

What is different about COB LED strips?

So-called SMD LEDs are used in previous LED strips. SMD stands for Surface Mounted Device, i.e. a component that is mounted on the surface. Since the components of the LEDs are individual, completely encased components, they are mounted one behind the other on a printed circuit board – with the appropriate spacing. This creates the optical impression of a chain of light points.

With COB strips, there are no completely sheathed LEDs. The individual light-emitting diodes are applied directly to the PCBs without a jacket. This means that significantly more LEDs can be installed closely packed next to each other. Once the LEDs are mounted on the strip, the surface of the LEDs is coated with the fluorescent layer, which again creates a better uniformity of the light image. Of course, if you look closely, you can see that even with COB strips there are “gaps” between the individual LEDs. However, this is only visible when the strips are dimmed.