Some general rules about Vias design

Vias are often part of the signal routing. They are vertical connections between layers to simplify trace routing around other components or when there is a high density of interconnections to be made (i.e. BGA,µBGA). As PCB trace, the PCB vias also have an associated parasitic capacitance, inductance and impedance. Below is some general rules about Vias design in PCB schematic layouting.

1. Blind/buried vias are smaller and act less as a discontinuity in HDI design. However, the typical PCB manufacturing cost for using blind/buried via technologies is 12% higher comparing with the same configuration PCBs which only using the normal through hole Vias (based on Quick‐teck 2012 PCB cost analysis report).
2. Place power/ground via near power supply pins of IC, so get the power supply path short.
3. Add ground vias nearby the area where high speed signal changes layer. This allows the return current flow near to the signal current flow, adding positive impact on EMI and signal integrity.
4. Via‐in‐pad design is better thermally than normal pad, but it could be the reason of pseudo soldering in the reflow soldering process.
5. For BGA and µBGA solder joints, it is suggested to use filled via if Via‐in‐pad design have to be accomplished.
6. High density vias can negatively affect the PCB mechanical performance. PCB twist/wrap check is recommended on this area.

Experienced via design knowledge will enhance the engineering performance, saving cost, increasing the stability of the products.  Above guidelines using in PCB design process are recommended.