Application Of Copper Foil Roughness To High Speed PCB

Application of copper foil roughness to high speed PCB

Do you care what kind of copper foil is used in high speed PCB design? And how is this reflected in the design document?

This issue of the problem, originally wanted to give everyone full marks, but after all, there is still a very good answer, in order not to let people feel that we are in and mud, or distinguish.

Yes, considering the roughness of copper foil, the signal rate on the board is needed first. Some people replied that the highest speed on my board is not more than 3Gbps, so there is no need to bother to consider it.

That's right. We also advocate doing the right thing when the right thing is done. PCB design is an art of tradeoffs. But as a follow-up knowledge supplement, understanding is still necessary.

Who knows what will happen in the future to design higher speed signals, and it's a trend that will only get higher and higher in the future, which is why the industry says it's springtime for simulation engineers.

Generally speaking, we recommend that the signal to more than 10Gbps can pay attention to the roughness of copper foil, but also to pay attention to what type of roughness of copper foil is used, in 5Gbps~10Gbps before whether to pay attention to the specific system.

As for how to reflect in the design, we generally have the following two forms:

1, in the drill information to define the cascade information, including the specific PP type, copper foil type;

2. Separate excel lamination information sheet, or board making information sheet, which defines specific lamination and impedance control requirements, and notes specific copper foil types in the lamination information.