Grow Light

A circular 12 V LED board designed for growing plants. The board uses a single-sided, 80 mm aluminum MCPCB with 20 red LEDs and 3 blue LEDs. A medium Daiso aluminum makgeolli cup serves as the heatsink and mechanical structure.

Project Status

• Current KiCad design: v1.0.3 (2026-07-27)
• Manufacturing order version: v1.0.2 (2026-07-11)
• Current phase: awaiting MCPCB production and delivery
• v1.0.3 change: added F.Silkscreen guides around the six M3 mounting holes and the central cable hole
• DRC: 0 active errors, 0 active warnings, and 0 unconnected pads
• Exclusion: one warning for the unavailable source library of an embedded silkscreen graphic

The design files in this repository are currently at v1.0.3. The previews below and the ordered MCPCB are v1.0.2. Manufacturing files for v1.0.3 have not been generated.

Specifications

Item	Specification
PCB	80 mm diameter, 1-layer Aluminum MCPCB
PCB thickness	1.6 mm
Copper	1 oz, F.Cu only
Surface finish	HAL SnPb
Solder mask / silkscreen	White / black, front side only
Power input	12 V from a USB-C PD trigger board
Target power consumption	Approximately 2 W to 4 W
LEDs	20 red and 3 blue
Resistors	Four 68 Ω and one 82 Ω, 2010 package
Track widths	1.2 mm power tracks and 0.6 mm LED interconnects
Mounting holes	Six 3.2 mm M3 NPTH holes
Cable hole	One central 5.3 mm NPTH hole

Because KiCad requires an even number of copper layers, the project represents the stackup as a 2-layer board. All electrical copper is on F.Cu; B.Cu is unused. The actual manufacturing structure is F.Silkscreen / F.Mask / F.Cu / thermal dielectric / aluminum base.

Electrical Configuration

Channel	LEDs per Series String	Parallel Strings	Total LEDs	String Resistor
Red	5	4	20	68 Ω
Blue	3	1	3	82 Ω

The 2010 resistor bodies act as physical jumpers to complete the single-sided routing. Twenty-four F.Cu copper zones around the LEDs provide electrical connectivity and local heat spreading. The aluminum core is the primary thermal path, so the design does not use B.Cu heat-spreading copper or thermal vias.

Design Images

PCB Layout — v1.0.2

Manufacturing Preview — v1.0.2

Assembled Board Preview — v1.0.2

Manufactured PCB

A photograph will be added after the MCPCB arrives. It will show the holes, solder mask, silkscreen, and surface quality.

Completed Assembly

A powered-on photograph will be added after the LEDs and aluminum cooling structure have been assembled.

Assembly and Safety

• The red IWS-L5056-UR-N3 and blue IWS-L5056-UB-K3 LEDs use opposite footprint polarities. Verify every LED before placement.
• Do not rely on cable colors. Measure the 12 V output and polarity with a multimeter before soldering the cable to J1 +12V and J2 GND.
• Fit a grommet or strain relief where the cable passes through the central hole.
• Apply electrically non-conductive UPSIREN UTP-8 in a thin, even layer between the PCB and the aluminum cup.
• Use insulating washers or nylon shoulder washers at the M3 mounting points.
• Before applying power and again after final assembly, verify that the aluminum structure and fasteners are not shorted to +12V or GND.
• The aluminum structure and external bracket, rather than the PCB, must carry the lamp's mechanical load.

Repository Contents

• plant led.kicad_sch: schematic
• plant led.kicad_pcb: PCB layout
• plant led.kicad_pro: KiCad project settings
• parts_list.md: parts, manufacturing, and assembly specifications
• to-do.md: production, assembly, and test status
• references/datasheets: LED datasheets

Manufacturing Gerber files are not included in the repository. The footprints: library is also stored in an external directory shared by multiple projects. To open the project in another environment, configure the same shared library path.

License

This project is licensed under the MIT License.