Not all PCB vias are equal, especially when current and heat are involved.

A via is essentially a small copper cylinder with electrical resistance.
When current flows through it, power is dissipated as heat (I²R loss). If the via is undersized, this heat can lead to plating cracks, solder joint failure, or even board damage.

Here’s what affects via reliability:

Through-hole vias
Provide better heat distribution across all layers and can carry higher current.

Blind and buried vias
Useful for routing density, but with lower thermal performance. Better suited for signals rather than power paths.

Microvias
Ideal for HDI designs and fine-pitch routing, but not recommended for high-current applications.

Practical design guidelines:
Increase via diameter for power nets
Use thicker copper plating when possible
Place multiple vias in parallel to share current
Avoid relying on a single via for high current

PCB design is not only about routing.
It’s about thermal management, current handling, and long-term reliability.