COB (Chip On Board)

Tech-LED COB (Chip-On-Board) LED Modules

Tech-LED’s COB (Chip-On-Board) LED products are high-power LED modules where multiple LED chips are directly mounted on a substrate to form one large, bright light source. These COB LEDs are designed for lighting applications requiring intense, uniform illumination from a compact area. Instead of having many separate LED packages, a COB integrates many small LED dies closely together on a single board (often ceramic or metal-core PCB), which is then encapsulated (usually with phosphor for white light or with silicone for clear emission) to act as a single luminous panel.

We offer COBs in a variety of configurations – from small COBs with 4–9 chips to large COB arrays with dozens of chips, in shapes like square, rectangular, or circular to suit different lamp form factors. COB LEDs are available in white (with various color temperatures), as well as in monochromatic colors (for horticulture, stage lighting, etc.). They represent state-of-the-art in LED integration, achieving very high lumen output and density, simplifying optical design (one light source vs many), and improving thermal management (one substrate to heatsink).

Features and Strengths of Tech-LED COB LEDs

High Luminous Flux

COB LEDs pack a large number of emitters, so they produce extremely high light output. Our COBs can range from a few hundred lumens (for small COBs replacing, say, a 25W bulb) up to several thousand lumens for larger COB modules (replacing 100W+ traditional lamps). For example, we have a 13.5 mm square COB with 16 LED chips that can deliver on the order of 3000+ lumens in cool white, suitable for high-bay lighting or streetlights. Because the emitters are distributed and all enclosed in one optic, the light mixes and emerges uniformly, which is ideal for directional lighting applications. High flux in a single source also means one COB and one optic (lens/reflector) can often replace an array of many discrete LEDs, simplifying luminaire design and reducing component count.

Uniform Light Emission

One of the key advantages of COB is the single, shadow-free light source. Since the LED dies are so closely clustered and share one large phosphor/silicone encapsulation, the COB appears as one continuous light-emitting surface (LES). This results in smooth illumination without the multiple shadows or pixelation that can occur when using multiple point LEDs. For instance, in a COB downlight, you won’t see multiple LED images, just one bright disc. Our COBs are engineered to have even phosphor coverage (for white) and even chip spacing, ensuring consistent color and intensity across the emitting area. This uniformity makes COBs preferred for applications like studio lighting or photography lights, where even illumination is critical.

Thermal Efficiency

In COB modules, the LED chips are directly bonded to a thermally conductive substrate (often ceramic or aluminum-core PCB). This creates a short thermal path from the junctions to the heatsink. Our COB designs use materials with high thermal conductivity so that heat is spread out and transferred efficiently. Additionally, having a single substrate means fewer interfaces (no solder joints of LED package to board for each LED), improving reliability under high-power operation. Many of our COBs can be driven at high currents (hundreds of mA per chip) because the overall thermal resistance is low. For example, a COB with 20 chips might handle 2–3A total drive easily if properly heatsinked, whereas trying to run 20 discrete LEDs at high current might face thermal bottlenecks. We provide detailed thermal pad layouts and recommendations to customers so they can properly mount COBs to heatsinks using TIM (thermal interface material) and achieve optimal cooling.

Simplified Assembly and Design

Using COB LEDs can greatly simplify luminaire assembly. Instead of placing and soldering dozens of small LED packages, a manufacturer can mount one COB unit. We offer COBs in formats that are easy to integrate – many have pre-soldered leads or solder pads for quick connection, and standard sizes that fit COB holders and optics from third-party suppliers. The optics industry has many reflectors and lenses specifically made for common COB LES sizes (e.g., 9 mm LES, 14 mm LES, etc.), and our COB product line aligns with those standards, making it straightforward to find a compatible optic. Moreover, by going with one COB, designers reduce points of failure (one component vs many), and assembly steps (just adhesive or screws for one module vs pick-and-place for many LEDs). For companies transitioning from traditional bulbs, COBs offer an almost drop-in solution: one round COB on an aluminum star board can mimic a filament lamp’s light center, enabling retrofits in classic fixtures.

Custom Multi-Wavelength COBs

While white COBs are most common, Tech-LED also creates multi-color COB modules. For example, horticulture lights may use COBs that integrate a mix of red and blue LED chips on the same board to produce a horticultural spectrum. We have delivered bi-color COBs (e.g., red + blue) that emit a purple grow light in a single module (no need for separate red and blue LED arrays). Similarly, for tunable white lighting, we make COBs that have intermingled warm-white and cool-white chips; by adjusting their relative drive, the user can achieve a variable CCT output from one COB (instead of two different COBs). These advanced COBs leverage our precise binning and placement to ensure even color mixing. We can also do segmented COBs (half one color, half another) if needed for specialized signals or effects. One example could be a COB UV + visible for a curing system that needs both UV light for curing and visible light for inspection – combining them on one board ensures they are coaxial and simplifies the lamp design.

Applications of COB LED Modules

General Illumination (Indoor)

COB LEDs are widely used in downlights, spotlights, and track lights for homes, offices, and retail. A COB can provide a single-point light that is easy to reflect or focus, creating a nice beam for accent lighting. For example, our 30 W white COBs appear in many ceiling downlights – replacing CFL or halogen bulbs – delivering equivalent light with a fraction of the power and much longer life. Retail lighting often uses COB spotlights (in track fixtures) to highlight merchandise with high-CRI COBs ensuring colors pop. The uniform output of COBs avoids multi-shadow issues on displays. Additionally, LED filament bulbs (the vintage-style bulbs with multiple linear LEDs) are somewhat being superseded by small COBs that mimic a filament’s glow in a single element. We offer very small COBs that can fit in candle bulb forms, providing a filament-like appearance when lit (by using a linear array of chips as a “filament”).

High Bay and Outdoor Lighting

For higher power needs, larger COBs are used in high bay lights (warehouse lights) and street lights. Instead of dozens of discrete LEDs on a board, modern fixtures often have one or a few COBs. For instance, a 100 W street luminaire might use four of our COBs in an array, each behind its own lens, resulting in a clean and efficient optical design with fewer components. High bay fixtures similarly might place one 50 W COB at the focus of a reflector to create a broad downward light. The high lumen output and good thermal handling of COBs make them suited for these applications where reliability at high power is crucial. We ensure our COBs for outdoor use can handle environmental stresses – e.g., our COBs are tested in accelerated moisture and thermal conditions to guarantee the silicone encapsulant does not yellow or crack over time outside.

Automotive Headlights

Some advanced automotive headlamp designs use COB-like LED arrays as the light source for low and high beams. While many use LED projector modules with discrete LEDs, there are designs with a single flat LED emitter (COB or similar) to simulate a filament at the focal point of a reflector. Tech-LED’s high-luminance COBs can be employed in such setups, yielding a uniform beam that’s easier to shape to DOT/ECE headlight requirements. The advantage is a more homogeneous beam pattern and simpler assembly than multiple LED sources requiring alignment. Additionally, adaptive matrix headlights can use COBs segmented into zones that turn on/off – while those are more specialized, our experience with multi-die modules positions us to contribute to such automotive lighting innovations.

Stage and Entertainment Lighting

In concert lighting, LED PAR cans and spotlights utilize COB LEDs heavily. A single COB RGBW module can produce any color wash on stage with high brightness and smooth blending, unlike older multi-LED “pixelated” PAR lights where you could see red, green, and blue dots. Our COBs, especially multi-color ones, allow fixtures to output a uniform field of light that is camera-friendly (no color fringing) – crucial for TV stage lighting. We produce COBs with special color LED mixes (like adding lime or amber to RGB to increase CRI and range of pastel colors) based on lighting designers’ needs. They love COBs because they behave more like a traditional lamp (single source) and fit into existing fixture designs. We also provide UV COBs for theatrical blacklights, offering high-power UVA in one module to flood a stage with fluorescence – replacing large arrays of low-power UV LEDs or fragile fluorescent tubes.

Horticultural Grow Lights

Commercial plant grow lights benefit from COB LEDs for similar reasons – a single intense source is easier to reflect and direct onto plants than a multitude of small LEDs. We have deep red + blue COBs specifically engineered for plant growth, which produce the magenta glow common in indoor farms, but as a uniform field. Alternatively, some growers prefer a full-spectrum white COB (for easier viewing and broad spectrum) augmented by discrete red LEDs; we supply high-PAR white COBs with enhanced 450 nm and 660 nm output for this purpose. These COBs run at high wattage (50–100 W each) so we design them with robust thermal pads, and they drastically simplify fixture design – one COB per module vs hundreds of individual diodes. The reliability of fewer components also means less maintenance in vertical farms or greenhouses.

Photographic and Film Lighting

For film shooting and photography, consistency and quality of light are key. COB LEDs with high CRI (90+ or even 95+) are used in LED panel lights and spot lights that are replacing traditional incandescent fresnels and HMI lamps on sets. Our tunable white COBs (mixing warm and cool dies) allow studios to adjust color temperature from warm indoor (~3200 K) to daylight (~5600 K) smoothly, with excellent color rendering across the range. The single-source nature ensures these lights cast a single shadow (important in video to avoid multiple shadows from multi-point sources). Additionally, these COB-based lights can be made flicker-free by using high-frequency drivers, enabling high-speed photography without banding. We collaborate with pro lighting companies to provide LEDs that meet these high CRI and stability requirements.

In essence, COB LEDs have become a cornerstone of modern lighting design, and Tech-LED’s offerings, bolstered by our research and expertise, ensure that our COB modules deliver on the promise of high efficiency, high quality, and easy integration. Whether it’s illuminating a home, a highway, a hydroponic farm, or a Hollywood set, Tech-LED COBs are lighting the way with brilliant, reliable performance.