Key Engineering Takeaways
- •High-current traces (motors, battery inputs) must be calculated via IPC-2152 to keep temperature rise under 10°C.
- •A continuous Ground Plane (Layer 2) directly under high-speed digital signals (Layer 1) creates tightly coupled return paths and minimizes EMI radiation.
- •Always add thermal relief spokes to pads connected to large copper pours to facilitate reliable soldering.
Prerequisites
- • Schematic reading
IPC-2152 Trace Width Calculations for High-Current Motor Tracks
Standard 1 oz/ft² (35µm copper thickness) PCB traces cannot handle motor currents without significant trace widening:
$$\text{Width } (w) \approx \frac{I}{k \cdot \Delta T^{0.44}} \cdot \frac{1}{t}$$
- For **1 Ampere** with 10°C rise: $0.3\,\text{mm}$ ($12\,\text{mils}$) trace.
- For **5 Amperes** with 10°C rise: $2.8\,\text{mm}$ ($110\,\text{mils}$) trace.
- For **10+ Amperes**: Use wide top/bottom polygon pours bridged with multiple parallel vias or 2 oz copper weight.
Tags:#PCB Design#KiCad#Hardware#EMI#Power Planes#Fabrication