LED PCB Assembly refers to the process of mounting, soldering and electrically connecting light-emitting-diode (LED) packages and their driver/control components onto a printed circuit board (PCB) that has been specially designed for high heat dissipation, so that the finished module can be powered and emit light immediately. Unlike conventional PCBA, LED PCB Assembly focuses on opto-thermal-electrical co-design:

• Substrate & thermal management
  • Aluminum-core (MCPCB), copper-core or ceramic substrates are used to conduct heat away from the LED junction.
  • Thick copper planes, thermal vias and TIMs lower the junction-to-ambient thermal resistance.
• Optical requirements
  • High-reflectivity white solder-mask (≥88% reflectance) is applied to maximize light output.
  • Phosphor dispensing or color-bin matching is controlled to keep chromaticity and CRI within spec.
• Typical process flow
  Incoming inspection -> solder-paste stencil printing (optimized for thermal pads) -> high-speed pick-and-place (polarity check) -> reflow soldering (peak 240-255°C, nitrogen atmosphere) -> AOI/AXI -> selective wave (if THT parts) -> optical & electrical test (luminous flux, color temp, junction temp) -> burn-in -> conformal coating (lens area masked) -> final QC & pack.
• Key applications
  Street lighting, automotive lamps, flashlights, surgical lights, TV backlights, high-resolution LED displays--anywhere high brightness, long life and good heat control are required.