to the United States 
Automotive, marine, and RV applications share three challenges: limited DC voltage (typically 12V), vibration, and exposure to temperature extremes. Our modules and drivers are well-suited to these environments, but component selection requires attention to voltage headroom and mechanical mounting. This guide covers the key decisions.
Voltage: The 12V Constraint
A 12V vehicle battery actually delivers 12.6–14.4V (engine running) and can sag to 11.5V or lower during cranking. This limits how many LEDs you can wire in series with a DC buck driver.
| Driver | Overhead | Max LEDs in Series (white, Vf ~3.2V) on 12V |
|---|---|---|
| PowerPuck | 2.0V | 3 LEDs (9.6V + 2.0 = 11.6V min) — tight but works |
| BuckPuck DC | 2.5V | 2 LEDs (6.4V + 2.5 = 8.9V min) — 3 LEDs needs 12.1V, marginal |
PowerPuck is the recommended driver for 12V systems because its lower overhead (2.0V vs 2.5V) gives more margin. Available at 350mA, 700mA, and 1000mA, non-dimmable only.
For 24V systems (trucks, larger marine), BuckPuck DC works well with up to 6 white LEDs in series.
Recommended Modules
| Application | Module | Why |
|---|---|---|
| Interior accent lighting | Star or Side Emitter, warm white (2700–3000K) | Compact, warm tone for ambiance. Side Emitters for indirect cove lighting. |
| Task/reading lights | Star or 10mm Square, neutral white (4000–4100K) | Good color rendering for reading. Optic-compatible for focused beam. |
| Exterior / deck lights | Tri-Star or Quad, cool white (5000–6500K) | Higher output per module. Cool white for visibility. |
| Underwater (marine) | Star with sealed housing (customer-provided) | Modules are not waterproof — must be enclosed. Green (530nm) or blue (470nm) for underwater visibility. |
| Navigation / signal | Star, red (627nm) or green (530nm) | Wavelength-specific for port/starboard signaling. |
Vibration and Mounting
Vehicle and marine environments vibrate. Thermal tape alone may fail over time under constant vibration.
- Use thermal adhesive tape or thermal epoxy to bond modules to the heatsink — adhesive mounting distributes contact pressure evenly and eliminates fastener loosening under vibration
- Secure driver wiring with strain relief — vibration causes wire fatigue at solder joints
- Choose “With Leads” driver variants rather than PCB Mount to avoid cracked solder joints on the driver board
Temperature Considerations
Engine compartments can reach 80–100°C ambient. LED modules are rated for junction temperatures up to 150°C, but output derates significantly above 85°C. At high ambient temperatures:
- Oversize the heatsink substantially (target 20–30°C rise instead of 40°C)
- Mount LEDs away from engine heat sources where possible
- Cold environments (marine, RV winter use) are not a concern — LEDs perform better when cold
Waterproofing
Our LED modules and drivers are not waterproof or sealed. For marine deck lighting, exterior vehicle use, or any wet environment, you must provide your own sealed enclosure. The electronics should be fully protected from water spray, condensation, and salt air.
