What is Aspect Ratio in PCB?
PCB aspect ratio is one of the key attributes of PCB design and manufacturing, which means the ratio of the thickness of the PCB by the diameter of the min hole (PTH or blind via) on the board.
Why is PCB aspect ratio so important?
It is known the plated holes are divided into through-holes and blind/buried vias, which are the soul of the entire PCB layout and the panel points of different layers. In the actual plating process, the thicker the PCB thickness, the smaller the holes, the more difficult it is for the plating solution to flow through the hole, while the harder for the center areas of the holes to get uniform plated (the low current areas).
Therefore, the higher the aspect ratio, the more difficult the plating, it often requires more advanced equipment, more expensive additives, and better manufacturing processes to achieve reliable plating. That's why when it comes to the capability of a PCB supplier, the PCB aspect ratio is always indispensable.
What is the conventional PCB aspect ratio?
The current conventional PCB aspect ratio in the PCB industry is 8:1 (PTHs), for example:
- When a thickness of 1.6mm, the min PTH is about 0.2mm,
- When a thickness of 2.0mm, the min PTH is about 0.25mm.
PS Electronics manufactured PCB from 1993, with industry-leading experiences, we now can expand the aspect ratio to 10:1 for PTHs, which means,
- When a thickness of 1.6mm, the min PTH is about 0.15mm,
- When a thickness of 2.0mm, the min PTH is about 0.20mm.
Meanwhile, for blind vias which are more difficult to process, we can also achieve ratio 1:1.