COB (Chip-on-Board) LED and SMD (Surface-Mount Device) LED are commonly used technologies of LED lighting. Both types of LED boast advantages of energy efficiency, durability and long lifespan. We will conduct a comprehensive comparison of these two LED based on luminous uniformity, brightness, energy efficiency, heat dissipation and lifespan. Finally, we will also provide a clear scenario-based selection guide and cost-budget analysis to help you easily make optimal decisions when engaging in home renovation, commercial space design, or outdoor lighting planning.
What is SMD LED Lighting?
SMD (Surface Mounted Device) LED refers to a technology characterized by "single chip + independent bracket + partial packaging". It involves encapsulating a single or a small number of LED chips in a "small-sized bracket" to form an independent "surface-mounted component". This component can be directly soldered onto a PCB (Printed Circuit Board) for use, featuring a clear layered structure, it can be understood as a "miniaturized independent light-emitting unit".
Owing to its structural characteristics, SMD LED is particularly suitable for low-power, flexibly arranged lighting applications, such as LED strips and small panel lights.
What is COB LED Lighting?
COB (Chip on Board) LED is defined by the technical configuration of "multiple bare chips + large-area substrate + integrated packaging". It involves directly mounting and fixing multiple bare LED chips (without individual packaging) onto a large-area substrate. After the circuit is connected through bonding wires, the entire assembly is fully covered and protected with encapsulate, forming an "integrated light-emitting module".
Its structure places strong emphasis on "integration and heat dissipation efficiency", can be understood as "directly converting multiple 'unpackaged chips' into a single 'large light-emitting module'". Owing to these structural characteristics, COB LED is particularly suitable for high-power, high-uniformity lighting applications, such as spotlights and high-power street lights.
What are the Different Between COB LED and SMD LED?
As mainstream LED packaging solutions, COB LED and SMD LED vary greatly in their design structures differences that directly impact their performance in light uniformity, viewing angle, energy efficiency, and heat dissipation. Below, we address typical queries to clarify how these two technologies stack up.
1. Does COB output smoother light than SMD?
SMD LED are made up of multiple individual LED chips, with relatively large physical gaps between them. These gaps tend to cause dark spots or brightness inconsistencies; when lit, their light emission is discontinuous, with individual light spots clearly visible to the naked eye, disrupting illumination uniformity.
In contrast, COB LED inherently have better light uniformity. They feature dozens to hundreds of LED chips directly and densely mounted on the same substrate, forming a continuous light-emitting surface via a shared phosphor layer and optical diffusion layer. This "surface light source" characteristic lets light diffuse uniformly over a large area; paired with the continuous application of fluorescent adhesive, the final light output is soft, free of discrete spots, and much more consistent.
2. How much brighter is COB over SMD?
COB LED gain a significant brightness advantage over SMD LED thanks to their multi-chip integrated design. Because of their structure of the chips are directly mounted on the substrate, which greatly reduces light loss from wire transmission and removes the optical structural limitations of SMD packaging. This design fundamentally boosts light output efficiency.
In terms of luminous efficacy (lumens per watt, lm/W), COB LED are generally 10%-30% more efficient than SMD LED. Industry data shows that typical COB lighting products achieve 100-200 lm/W, with some high-end models even exceeding 200 lm/W. By contrast, SMD LED usually only maintain 80-150 lm/W, meaning there is a notable gap in energy-to-light conversion efficiency between the two.
When it comes to brightness performance, COB LED’ multi-chip integration further cuts down light loss. Not only do they deliver higher brightness per unit area, but in real-world applications, their brightness can be 20%-50% higher than SMD LED at the same power level.
3. Does COB have a wider angle than SMD?
COB LED feature a surface light source design, where multiple chips are directly integrated onto a substrate and covered with an overall silicone lens. This structure eliminates the obstruction caused by traditional brackets and bonding wires, so the light can diffuse directly outward from the chip surface in all directions, resulting in a theoretical beam angle of nearly 180°.
By contrast, each individual SMD LED chip is housed in a separate bracket with a reflective cup, sitting at the bottom of the cup. Light must pass through the lens at the cup’s opening and refract before emission. While SMD LED can be optimized for focused light through lens design (e.g., narrow beam angles of 15°-60°), their beam angle is inherently limited by the cup structure. Typically, standard SMD LED only achieve a beam angle of 120°-140°, with a noticeable drop in brightness at the edges of the light beam.
4. Is COB more energy-efficient than SMD?
When the same brightness level is required, COB LED are generally more energy-efficient than SMD LED and this advantage comes from COB’s optimized structural design.
On one hand, COB integrates chips directly onto the substrate, eliminating the obstructive components like wires and brackets used in SMD packaging. This significantly reduces light loss during emission. On the other hand, COB’s fluorescent adhesive layer covers the chip surface evenly, boosting light-color conversion efficiency. It also avoids the "light waste" issue common in SMD LED which stems from the large gaps between individual LED chips.
In terms of specific luminous efficacy data, SMD LED typically range from 100 to 150 lumens per watt (lm/W). By contrast, COB LED can reach 180 to 220 lm/W, with high-end COB products in laboratory settings achieving even higher efficacy.
5. Does COB LED have better heat dissipation and lifespan than SMD LED?
An LED’s heat dissipation performance directly affects its efficacy degradation and service life.
Starting with the core thermal resistance index: COB LED have a thermal resistance coefficient of only 1.2–2.5°C/W, while SMD LED reach as high as 5–8°C/W.
Under the same power conditions, COB chips connect directly to the heat-dissipating substrate through thermal conductive adhesive or solder, resulting in a short heat transfer path. This allows the junction temperature (Tj, a key indicator of LED thermal performance) to be stably controlled below 85°C. By contrast, SMD LED rely on pins and pads for indirect heat dissipation, which easily leads to localized heat accumulation, their junction temperature may even exceed 110°C.
Additionally, the substrate area of a COB module is far larger than that of a single SMD LED chip, further enhancing heat dissipation efficiency and slowing down light decay during long-term use.
In practical terms, under the same operating conditions, COB LED typically have a 10%–20% longer service life than densely arranged SMD LED, all thanks to their more stable heat dissipation.
How to Choose the Right LED: COB or SMD?
When deciding between COB LED and SMD LED, the core step is to first clarify your application scenario and key requirements (such as luminous uniformity, power, cost, installation and maintenance, etc.). The two technologies differ fundamentally in structure and performance, and are suited for entirely different use cases. Below is a detailed breakdown from two perspectives: a "Scenario-Based Selection Guide" and a "Cost & Budget Selection Guide" to help you make an accurate decision.
1. Scenario-Based Selection Guide for LED: Should I Choose COB or SMD?
For Indoor Lighting, luminous uniformity and visual comfort should be prioritized.
- For ceiling lights, panel lights, downlights without main lights, or commercial space lighting, COB LED are preferred. They emit light uniformly without dark areas, have low glare and high color rendering, which can meet the needs of long-term close-range lighting and restoring the color of goods.
- For light strips, ambient lights, or economical lighting fixtures, SMD LED are more advantageous due to their small size, bendability, and low cost in medium and low power applications, making them suitable for decorative and basic lighting needs.
For Outdoor Lighting, weather resistance, power and reliability are crucial.
- For high-power floodlights, COB LED are the better choice as they have high single-chip power, stable heat dissipation, and slow light decay under long-term high-load operation.
- For low and medium-power streetlights, garden lights and outdoor decorative lights, SMD LED are more suitable. Their packaging is well-sealed, with strong resistance to rain, dust, and vibration. They can also flexibly adjust the irradiation angle or adapt to string-like and strip-like shapes.
In Special Scenarios, the choice should be combined with customized requirements.
- In industrial lighting, for high-brightness and large-range uniform illumination, COB is selected, while for local supplementary lighting, SMD with flexible installation is preferred.
- In medical lighting, COB must be chosen because of the need for high color rendering and shadowless light spots.
- In automotive lighting, for daytime running lights and tail lights, SMD with a small size and bendability is given priority and for high-power headlights, COB can be selected, but it needs to be equipped with a professional heat dissipation design.
2. Cost-Budget Guide: Which is Better SMD or COB LED？
In terms of initial procurement costs, SMD LED hold a price advantage at equivalent power levels. Thanks to their mature single-chip packaging technology and large-scale mass production, SMD LED cost 33% to 40% less than COB LED. However, this advantage shifts to COB LED in high-power scenarios (50W and above): SMD systems require dense arrays of multiple chips paired with additional heat sinks, making their total cost higher than COB solutions, which avoid the need for dense chip layouts.
Long-term hidden costs primarily stem from maintenance and energy consumption:
- Maintenance: If a single SMD chip fails, it can be directly replaced by re-soldering, resulting in low repair costs. For COB LED, chip failure typically requires full replacement of the entire light board, with maintenance costs 5 to 10 times higher than SMD.
- Energy consumption: COB LED offer 5% to 10% higher luminous efficacy than SMD LED at the same brightness, translating to significant electricity savings over time.
When balancing initial and long-term costs, cost-effectiveness varies by scenario:
- For short-term use or low-power applications (e.g., household table lamps, temporary decorative lighting), SMD LED are more economical. They save on upfront costs and replacement costs remain low if failures occur.
- For long-term use or high-power applications (e.g., commercial spotlights, outdoor garden lighting), COB LED provide better overall value. Despite slightly higher initial investment, their energy efficiency and longer lifespan reduce total ownership costs significantly over time.
SMD LED & COB LED: Complementary Partners, Not Replacements
SMD LED and COB LED are never "either-or" alternatives, instead, they act as "lighting partners" that each bring their strengths to the table:
- For home renovation lighting selection, the flexible adaptability of SMD LED and the uniform light spots of COB LED can be combined according to specific needs.
- For DIY enthusiasts building supplementary lighting setups, the easy-to-solder advantage of SMD LED and the high-brightness feature of COB LED need to be precisely matched to the project’s requirements.
- For commercial procurement, it is even more essential to balance cost and lifespan by considering the actual application scenario.
If you’re still unsure about the right choice for specific use cases, such as which type to pick for industrial lighting or how to select spotlights for retail stores, you can browse our store for more inspiration or contact us to customize a tailored lighting solution.
