PCB Principles of Vias
In this article, EPCB will go over some useful PCB principles of vias, and hope it may work for you.
Based on our past experience, we find that vias often bring a lot of negative effects in high-speed PCB design. In order to reduce negative effects in PCB design, you can follow our suggestions listed as below:
1. Take the cost and signal quality into consideration, you have to choose the most suitable via size. For example, it is better to choose a 10/20Mil via for a 6~10 layer memory module PCB, or it is better to choose an 8/18Mil via for some high-density small-size board. Actually, 6mil via can meet ordinary PCB requirement.
2. Vias should be close to pin of power and ground, leads between vias and pins are as shorter as better, because they will cause increased electrical inductance. Besides, the thicker the wire of power and ground is, the less can impedance it has.
3. In order to close to the electrical loop, you can place some vias near the place where signal exchange. Or you can place a large number of redundant ground vias on a PCB.