Heavy copper PCBs for high currents

Heavy copper PCBs: when 1 oz simply isn't enough

Not every PCB is made for high currents.

Standard circuit boards typically use 1-2 oz copper, but for higher power designs this is often insufficient.

What is a heavy copper PCB?

A heavy copper PCB uses >=3 oz copper on all layers (inner and outer layers). This makes it possible to handle higher currents safely and reliably.

Why heavy copper?

-> Higher current capacity Thicker copper can carry significantly more current than wider traces alone. -> Better thermal performance Resistant to repeated thermal cycles during assembly and use. -> Mechanically more robust Stronger plated-through holes and connector zones, less chance of failure. -> Effective heat dissipation Suitable for power electronics with high power losses.

But: keep lead time in mind

Heavy copper PCBs have longer production times and are more complex (and expensive) to manufacture. (1-2 oz copper: 24 hours and 4 oz: 3 weeks)

In many projects, it therefore makes sense to first use a PCB with thinner copper layers to: -> test the majority of the circuit -> validate functionality, timing and interfaces -> develop software and control systems Only then do you switch to heavy copper for the final power section.

ProtoPCBALabLearning

Heavy copper is not a first step, but often a final optimisation. Smart prototyping means: first learn with what is fast and manufacturable, then scale up to what will be heavily loaded.

HappyEngineering