Drone PDB Designing

Engineering a compact, high-current PDB with thermal efficiency and structural simplicity.

When it comes to designing drones, especially high-performance ones, the power distribution board (PDB) plays a critical role in ensuring efficient, reliable power delivery to the electronic speed controllers (ESCs), motors, and other subsystems. One of the biggest challenges in designing such a PDB lies in managing high current loads while also accommodating mechanical mounting constraints — especially when single-side soldering is a necessity.

The Core Challenge: Single-Side Soldering

In compact drone designs, especially racing or FPV drones, space optimization is everything. Mounting constraints often mean that there's limited clearance on one side of the PCB. This prevents components or solder joints from protruding on both sides. As a result, single-side soldering becomes essential. But this seemingly simple decision introduces a cascade of design complexities, particularly in routing high-current traces efficiently on a single side.

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Why Single-Side Soldering Matters

Compact assembly: The PDB often sits sandwiched between other components such as flight controllers or frame parts.
Managing heat dissipation and current density on a single layer presents engineering hurdles — especially when dealing with 200A of peak current draw.

The Heat Dissipation Problem

High current inherently leads to heat generation. If not managed properly, this heat can degrade performance, cause voltage drops, or even damage the PCB. Copper traces alone may not be sufficient to carry such high current safely on a single side. That’s where vias come into play.

The Smart Solution: Array of Vias for Current Sharing and Heat Dissipation

  • Efficient Heat Dissipation: Vias act as thermal pathways. They help transfer heat from the high-current traces to the opposite side and distribute it more evenly across the board, preventing hotspots.
  • Minimized Voltage Drop: By reducing resistance using multilayer routing via vias, voltage drops are kept in check, ensuring stable performance even under full throttle.
  • Redundancy and Reliability: An array of vias rather than just a few ensures that even if one or two fail or degrade over time, the board continues to function safely.
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Proven Performance: 200A Handling

The final PDB design was rigorously tested and optimized to handle up to 200 amps of continuous current, while keeping the temperature below 75°C at the soldering pads — even under sustained loads. This was achieved through:

  • Use of 3 oz copper layers for improved conductivity
  • Wide power planes and minimal trace bottlenecks, placed in a circular pattern to avoid Net antenna effect
  • Densely packed via arrays directly under high-current solder pads