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Electronics => PCB/EDA/CAD => Topic started by: newtekuser on November 01, 2024, 03:49:25 pm

Title: Adjusting PCB layer thickness for short return path
Post by: newtekuser on November 01, 2024, 03:49:25 pm
I need some input on the values chosen for me by KiCad on my 4 Layer PCB setup. My goal is to bring the ground planes closer to my signal and power planes to have a good short return path. Are the suggested values for thickness good?





Title: Re: Adjusting PCB layer thickness for short return path
Post by: tggzzz on November 01, 2024, 04:15:37 pm
I need some input on the values chosen for me by KiCad on my 4 Layer PCB setup. My goal is to bring the ground planes closer to my signal and power planes to have a good short return path. Are the suggested values for thickness good?

Your PCB fabrication house will specify the stackup(s) they can make. Use those figures.
Title: Re: Adjusting PCB layer thickness for short return path
Post by: Kurets on November 01, 2024, 04:17:26 pm
Unless you are buying large quantities of PCBs it is unlikely that you can specify the layer stackup freely. Go to your preferred supplier JLPCB, WE Direkt, etc. and look what their standard stackup for a 4-layer board is.

In any case, just having ground/vcc on inner layers will be good enough. The only reason to care about the specific layer separation is if you are trying to do controlled impedance traces for RF or very high speed digital interfaces.
Title: Re: Adjusting PCB layer thickness for short return path
Post by: newtekuser on November 01, 2024, 05:10:06 pm
I need some input on the values chosen for me by KiCad on my 4 Layer PCB setup. My goal is to bring the ground planes closer to my signal and power planes to have a good short return path. Are the suggested values for thickness good?

Your PCB fabrication house will specify the stackup(s) they can make. Use those figures.

I know my fabricator (JLC) can manufacture this stackup configuration because they have already produced it for me, but I was wondering if I could improve on it. Based on Kurets' reply I should be good already.
Title: Re: Adjusting PCB layer thickness for short return path
Post by: tggzzz on November 01, 2024, 07:41:00 pm
JLC can (apparently; I havn't used  them) do many different thicknesses and stackups.ma

The question is then why one of them wouldn't be satisfactory. If there is an answer to that, then choose another.
Title: Re: Adjusting PCB layer thickness for short return path
Post by: thm_w on November 01, 2024, 08:57:21 pm
You choose from the list here: https://jlcpcb.com/impedance