Modern LED strips: types and how to choose

The LED strips in the 2K-Trade catalogue fall into several families that differ in how the diodes are built, the light effect they give and the way they are controlled. This text puts them in one place: what SMD, COB, CCT, RGBW and “digital” mean, one example model from each group, and where that strip goes in a stretch ceiling. Full model tables for COB and digital strips are in the article COB and Digital 24V LED Strips: Technology, Models and Applications.

LED strip families at a glance

All the models listed run on 24 V DC. The parameters come from the product cards in the LED strips category.

SMD 2835 — the basis of the range

An SMD strip has individual diodes placed on the board at equal intervals. Without a diffuser the dots are visible; with a matt diffuser or behind a membrane the light is even. Example model: LED strip 140 LED/m 24V SMD-2835 IP20 — three power variants of 4.8, 9.6 and 14.4 W/m, colour 3000, 4000 or 6000 K, 8 mm board. In a stretch ceiling this is the typical strip for perimeter lighting in niche profiles and for backlit ceilings (light boxes), where the membrane blurs the diode dots.

COB — a continuous line of light

In a COB (Chip-on-Board) strip the diodes are densely packed and covered with a common phosphor layer, so the strip glows as a continuous line without visible dots — even in a profile with no diffuser or with a clear cover. Example model: LED COB 320 LED/m 24V IP20 — 10 or 14 W/m, colour 3000, 4000 or 6000 K, CRI ≥ 90, 8 or 10 mm board. In a stretch ceiling COB is the first choice for light lines in the GAMMA 20, 30 and 50 profiles, where the number in the name is the approximate width of the light line in millimetres.

CCT — white with adjustable temperature

A CCT strip has two kinds of white diodes — warm and cool — and a CCT controller mixes their proportions, so the colour changes smoothly within a single strip. Example model: LED strip COB CCT 608 LED/m 24 V IP20 — 16 W/m, range 2700–6000 K, CRI ≥ 95, 10 mm board. In a stretch ceiling CCT is used in GAMMA light lines where the same room should be lit cooler in the morning and warmer in the evening.

RGB and RGBW — coloured light

An RGB strip has three channels in each diode — red, green and blue — and gives the full colour palette; RGBW adds a separate white channel (4000 K or 6000 K in the catalogue). Example model: LED strip RGB 60 LED/m 24V SMD-5050 IP20 — 14.4 W/m, 10 mm board. In a stretch ceiling colour most often goes into perimeter lighting and niches as decorative rather than main lighting.

Digital (addressable) — segment control

A digital strip has built-in control ICs, so each segment can be lit separately: running light, sequences, gradients. It requires an SPI controller — an ordinary RGB or CCT controller will not drive it. Example model: Digital LED strip WS2811 COB 360 LED/m 24V IP20 — 11 W/m, white 3000, 4000 or 6500 K, CRI ≥ 90, 10 mm board; 24 V DC supply like the other models in the catalogue. In a stretch ceiling digital strips are installed in GAMMA lines and on staircases.

IP65 — damp rooms

In the IP65 version the diodes are encased in a flexible resin that protects them from dust and splashes. Example model: LED strip 140 LED/m 24V SMD-2835 IP65 — 9.6 W/m, colour 4000 K, 8 mm board. In a stretch ceiling this is the choice for bathrooms, kitchens, garages and covered terraces.

How to choose an LED strip

• 24 V for long runs. At the same power a 24 V strip draws less current than a 12 V one, so the voltage drop along the length is smaller and the end of the run is as bright as the start.
• IP rating by installation location. IP20 for dry interiors, IP65 for bathrooms, kitchens, garages and covered terraces.
• CCT or fixed white. If there is to be one colour, a mono strip (3000, 4000 or 6000 K) and a dimmer are enough. If the colour is to change, you need a CCT strip and a CCT controller.
• A controller matched to the strip type. Mono — dimmer, CCT — CCT controller, RGB/RGBW — three- or four-channel controller, digital — SPI controller. See the Drivers for LED strips category.
• A 24 V power supply with a power reserve. Power supply rating = strip length [m] × power [W/m] × 1.2. Example: 10 m of COB strip at 14 W/m needs a power supply of at least 168 W. See the LED power supplies category.
• Board width and the profile. Strips have an 8, 10 or 12 mm board; check the width of the profile channel before ordering.

Frequently asked questions

What is the difference between a COB and an SMD strip?

A COB strip has diodes covered with a common phosphor layer and glows as a continuous line without dots, even without a diffuser. An SMD strip has individual diodes at equal intervals; with a matt diffuser or behind a membrane the difference is small.

Do digital strips also run on 24 V?

Yes. The Digital LED strip WS2811 COB 360 LED/m from the 2K-Trade catalogue has a 24 V DC supply, like the other models. The difference is in control: a digital strip requires an SPI controller, not an ordinary RGB controller.

Which strip should I choose for a light line in a stretch ceiling?

For light lines in GAMMA profiles — the COB 320 LED/m strip, which gives a continuous line without dots. If the white colour is to change during the day — the COB CCT 608 LED/m strip with a CCT controller.

Can an LED strip be installed in a bathroom?

Yes, in the IP65 version — for example the LED strip 140 LED/m 24V SMD-2835 IP65. The diodes are encased in resin that protects them from dust and splashes. IP20 strips are intended for dry interiors only.

Author: MB 2K-Trade