Managing Spillover Light in LED PCBs

One often-overlooked issue in LED circuit design is lateral and rear light emission—commonly referred to as spillover light. This unintended light loss can significantly impact the brightness and effectiveness of the final product. A commonly used strategy is applying a white solder mask to reflect stray light outward. However, not all white masks are created equal. Many lose their reflective qualities during the reflow process due to heat exposure—becoming dull, thinner, and even semi-transparent, which reduces their ability to reflect light effectively.

Hitech Circuits addresses this by applying a highly durable and thermally stable white solder mask. Our go-to choice is Taiyo’s LEW1, a market-leading product known for maintaining its brightness and structural integrity even after undergoing multiple heat cycles. Unlike conventional options, LEW1 resists yellowing and maintains optimal reflectivity, ensuring consistent lighting performance across all environments.

Advanced Thermal Management for High-Power LED Boards

Heat dissipation is one of the most critical challenges in high-power LED systems. Excessive heat can degrade LED lifespan, shift color output, and damage components. Metal Core PCBs (MCPCBs) offer an effective solution by providing a direct thermal path from the heat-generating components to the ambient environment.

We utilize high-performance substrates from trusted manufacturers such as Thermagon, Bergquist, Arlon, and Univaco. These materials enhance thermal conductivity, but the key to optimal performance lies in how the heat moves from the LED component, through the dielectric, and into the metal core. This transition is heavily dependent on the type, thickness, and bonding quality of the prepreg.

At Hitech Circuits, we precisely select a prepreg material that’s thin enough to allow efficient heat flow yet thick enough to guarantee proper dielectric insulation. This ensures both electrical reliability and thermal efficiency, especially in densely populated or high-current designs.

Elimination of Air Voids: A Hidden Performance Enhancer

Even the finest materials can underperform if improperly bonded. One often underestimated issue is the presence of air bubbles within the dielectric layer. These voids act as thermal insulators, trapping heat and hindering dissipation.

Hitech Circuits employs a specialized lamination process that eliminates insulating air gaps between the metal base and the dielectric layer. This technique dramatically improves heat transfer efficiency and enhances the overall reliability of the board—especially under continuous high-power operation.

Additional Engineering Considerations

In addition to heat and light considerations, successful LED PCB fabrication also includes:

• Copper Weight Optimization:Choosing the right copper thickness ensures sufficient current-carrying capacity while managing heat generation.
• Via Design: Thermal vias can be strategically added to improve vertical heat conduction from the component side to the core.
• Surface Finish Selection:We offer ENIG (Electroless Nickel Immersion Gold), HASL, and other finishes to match your LED application’s reliability and solderability requirements.
• Circuit Layer Patterning:Custom circuit traces are designed with minimal resistance paths and optimized spacing for high-frequency or high-current LED arrays.

Applications of LED PCBs

LED PCBs are widely adopted in industries requiring high-performance lighting, energy efficiency, and compact design. These include:

• Lighting:Commercial and residential LED lighting, automotive headlamps, architectural accent lighting, and outdoor displays.
• Consumer Electronics:LED modules in televisions, monitors, and home appliances.
• Telecommunications:Network equipment with status indication lighting or signal-processing boards.
• Automotive Systems:Brake lights, dashboard displays, and control modules.
• Medical Devices:High-intensity surgical lighting, portable diagnostic tools, and equipment indicators.
• Industrial Equipment: Machine vision systems, floodlights, and factory automation modules.

Let’s Build Smarter, Brighter PCBs Together

At Hitech Circuits, we combine years of manufacturing experience with cutting-edge materials and technology to provide LED PCBs that exceed performance expectations. Whether you need a one-off prototype or full-scale production, our team is here to try our best to support you.

Send your Gerber files or inquiries to sales3@hitechcircuits.com. Let us help bring your LED innovations to light—efficiently, reliably, and brilliantly.