Types of Vias Allowed on a 4-Layer PCB Design

When designing a 4-layer PCB, it’s important to consider the types of vias that are allowed for optimal functionality.

For the top (1) and bottom (16) layers, it is recommended to use them for signaling purposes. The upper middle layer (2) can be designated for GND, while the lower middle layer (15) can be used for power distribution.

When it comes to connecting signal traces between layers, through-hole vias are ideal, going from the top layer to the bottom layer. However, for GND and power connections, blind vias such as 1-2 and 1-15 types are preferable.

Here is an illustration of how the vias should be strategically placed:

After reviewing design rules from various PCB manufacturers, it seems that through-hole vias (1-16) are commonly allowed. However, the freedom to use specific types of blind vias may vary.