Define the light source and circuit roles
An LED PCB carries the electrical connections and mechanical interfaces for the selected light source and associated circuitry. Start with exact LED part numbers, operating current, driver behavior and the required optical output. A forward-voltage label alone does not define a suitable power source or current-control method.
SMD LEDs are packaged devices placed on board lands. Chip-on-board constructions use die-level attachment and interconnection in a defined module process. Driver-on-board describes integration of driver circuitry; it is not another LED package style. Each approach has different manufacturing and test requirements.
Choose the substrate from the complete heat path
FR-4, metal-base and ceramic constructions can be candidates depending on the circuit and cooling needs. Compare the component attachment, spreading region, dielectric where present, base and heatsink interface. Do not select a board solely from the metal’s bulk thermal conductivity.
Use the LED supplier’s package and temperature guidance, then validate the assembly in its actual enclosure and mounting arrangement. Current, ambient conditions and cooling influence the operating temperature and optical behavior. A bare board cannot be assigned a universal 100 W or 200 W luminaire rating from its outline alone.
Coordinate optical and electrical requirements
Specify wavelength or color characteristics, binning requirements, optical geometry and the relevant measurement conditions. Lens position, reflector clearance and board surface appearance may affect the result. For horticultural lighting, define the required spectral and photon-output measures rather than relying only on a human-vision brightness description.
Review current distribution, connector capacity, protection and dimming behavior. Circuits with hazardous voltages require a qualified product-level insulation and safety design. Combining a driver and LEDs on one board does not itself establish isolation or compliance.
Plan the assembly for the selected package
Use the exact land pattern, thermal-pad connection and handling requirements. Coordinate paste volume, component orientation, thermal profile and inspection with the assembler. Avoid contact or contamination that can damage optical surfaces or change light output.
A COB manufacturing request must identify whether the scope is bare-die processing, procurement of an existing COB module, or mounting that module to another assembly. Die attach, wire bonding and encapsulation require separately confirmed processes; they are not implied by a standard SMT service.
Review flexible strips and mechanical mounting
For a flexible LED strip, define installed geometry, bend locations, power-feed arrangement and attachment to the intended support. Voltage drop and heating can vary along the circuit. Keep bending away from components and joints according to the approved construction, and do not assume the adhesive layer provides every required thermal or mechanical function.
For rigid boards, check fastener access, flatness, interface materials and the optical alignment after installation. Validate the populated assembly, not only the bare board, against the mounting and enclosure drawing.
Release with an inspection and test plan
The inquiry package should include circuit files, BOM and LED bin requirements, assembly drawings, thermal interfaces, quantities and electrical/optical acceptance criteria. Distinguish visual workmanship checks from measurements of current, temperature and light output.
Investigate defects by correlating placement, soldering, electrical and optical evidence. A dark LED may result from polarity, a damaged device, an open connection or driver behavior. Record first-article results and approved changes so repeated builds use the same validated configuration.