COB (Chip on Board)
A dense array of LED chips bonded directly to a substrate, producing a seamless, dot-free light output. Used in high-end strip lights and downlights.
COB stands for chip on board — instead of individual LED chips spaced apart on a circuit board, COB packs hundreds of tiny LED dies directly onto the substrate with no gaps. The result is a continuous, uniform light source with no visible dots or hotspots.
For strip lights, COB has been a game-changer. Traditional SMD strips show visible individual LED dots, especially when mounted without a diffuser channel. COB strips produce a perfectly smooth, continuous line of light — the kind of clean glow you see in high-end architectural and retail installations. They typically run 300-500+ LEDs per meter compared to 60-120 for SMD.
The trade-offs are heat and cost. COB strips generate more heat per meter than SMD strips at the same brightness, making aluminum channel mounting more important for longevity. They're also more expensive — roughly 2-3x the price of equivalent SMD strips. But for under-cabinet lighting, cove lighting, and any application where the strip is visible or reflected off a surface, the seamless output is worth the premium.
Specifications
| Light quality | Seamless, no visible dots |
| Density | 300-500+ LEDs per meter |
| Best for | Under-cabinet, cove lighting, accents |
Related Terms
- SMD (Surface Mount Device)
A type of LED chip soldered directly onto a circuit board. Common in strip lights — the number (2835, 5050) indicates the chip dimensions in tenths of millimeters.
- LED Density
The number of LED chips per meter on a strip light. Higher density produces smoother, more even light with fewer visible dots. Common values: 30, 60, 120, or 144 LEDs/m.
- LED Channel
An aluminum housing that mounts LED strips for a professional finish. Includes a diffuser cover that eliminates visible LED dots and improves heat dissipation.