In recent years, the technology around PCB design has advanced rapidly and while high speed PCB design was once not thought to be possible, the opposite is now true. Here, we are taking you through our top tips for high speed PCB design.
Have A Plan
The first thing that you will need to do before starting your high speed design process is, of course, come up with a plan. When you try to process without a plan, you will tend to find that you run into more issues and experience more setbacks. Have a checklist of questions to ask yourself throughout your PCB design. This should include things such as system organisation, signal speed, power supply and complex signals.
Document The Board Stackup
Once you have a plan in place, it is then time to define and document your layer stackup requirements thoroughly. At this point, we would recommend meeting with your manufacturer to discuss what materials will be used on your board and any constraints you need to input into your design rules.
Implement Maximum Shielding Benefits
The last thing that any PCB designer wants for their high speed board is to have two signals interfering with each other or a nearby component. To reduce the risk of this happening, you will want to try and maximise as much as you can the shielding benefits for the signals.
Here, you should try to keep as much distance as possible between your signal traces and you may even want to look at routing signals on a separate layer. When you are routing signals on these various layers, you will want to route them orthogonally to each other and for high speed PCB design you can use an interactive routing datasheet to do this.
With interactive routing, you can design the very best PCB layouts, but in just a fraction of the time as it will allow you to work on multiple layers at the same time whilst you adhere to any design constraints.
Ensure There Is An Efficient Path For Current Return
With any high speed PCB design, the signals will look for a route from source to sink along the path which impedes them the least. For some items, you may need to do this with a via, as this will ensure a smooth path of travel.
Not doing this could lead to currents leaking through splits in the ground plane which then leads to a loss of signal integrity.
For those of you who will be using vias to return currents to their termination, you need to ensure that these are tightly coupled and that the impedance matched differential vias as this is what will make sure that signals arrive promptly. When placing these return vias, you should return them as close as you possibly can to your signal vias as this will shorten the distance of how far it has to travel.