Data for check the impedance

For checking the impedance in my PCB (i’m not expert) I wanna fix this data on my project but i don’t find where i must write it.
Someone can help me?

This part of your screenshot:

suggests that “B” is two layers of prepreg, but it depends on your PCB stackup. You can set these paremeters in: PCB Editor / File / Board Setup / Boad Stackup / Phisycal Layers but anythig you set there are only mild gussestions. The final / Real stackup will depend on your PCB manufacturer and the choices you make while ordering PCB’s.

Thank you for your rapid answer but from the picture… B seems not the height of PCB but only the dietrelic between 2 layers.

No, it’s the dielectric between three layers, because there is a track in between, and therefore I wrote: “two layers of prepreg”. There will be a seam at the height of the center track, where the two prepreg layers are fused together.

Also, in general you do not have much control over the “T” thickness (PCB manufacturers have a fixed amound of copper thicknesses), but the “W” width parameter is the normal track width in KiCad.

Also, if controlled impedance is important to you, you should always communicate with your PCB manufacturer. There will always be small differences between manufactures and combination of materials. It is also common to make tests PCB’s to verify that controlled impedance tracks are within specifications.

But it’s up to you. You can buy cheap PCB’s and cross your fingers it is good enough (Or iterate to get it good enough), or you can order PCB’s with guaranteed impedance parameters, and those cost extra.

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