How to Select the PCB Material for Design

[Ashish1710]

On which criteria how to Select the PCB Material for any Design

[robertferanec]

Usually you select the PCB manufacturer first and then use what they offer. They usually have suggested stackups built from the materials they stock and use.

Building your own PCB stackup from the materials you select would be super expensive - many PCB manufacturers only stock selected materials and if they would need to buy some new that would be expensive + they have to experiment how the material will behave during pcb manufacturing process .. that makes it even more expensive.

[Ashish1710]

Yes @ robertferanec. If I working on high speed design(more than 2Ghz) so which material I chose for my design.

[qdrives]

Ashish1710 The amount of questions you ask about this makes me think the answer for this question is simple: FR4.

[Ashish1710]

qdrives Means For High speed design like frequency more than 2Ghz . Is the FR4 best material for more than 2Ghz frequency.? Or is there any other material I will use.

[qdrives]

Ashish1710 Over 2GHz is not a question for me. I only did low speed designs < 1GHz (signal rise time).
If you want accurate answers, you need to provide more details, like the speed (rise time), current, voltage, temperature, loss factor, (transmission) line lengths, etc.
You mention "more than 2GHz" - are you working on 2.4GHz (WiFi, Bluetooth, etc.) or way higher (>= 10GHz).
As far as I know, most 2.4GHz designs still use FR4.

[Ashish1710]

Thanks for the information.

[robertferanec]

I would still talk to the PCB manufacturer, they will tell you what material they use for the frequencies you need. You really don't want to select material by yourself for the reasons I mentioned in my previous post.

If I understand right, one of the biggest problems with "standard FR4" is loss. So maybe it will not be a problem in your case if your board is small or tracks are short.

This may also help: https://electronics.stackexchange.co...(e.g.%20Rogers).

[Ashish1710]

Thanks @robrtferanec.

[qingyeyu]

I think I should choose FR4，Its performance is much more stable than fr2/fr3, and the insulation grade and temperature resistance grade are very suitable, and the cost performance is also high.Take a look at the parameters of fr4 here

[qdrives]

qingyeyu Oh yes, that is easy. Always pick FR4 over FR2 and FR3. I do believe that the original question was more related to say Rogers material.

[binayak]

Ashish,
Is it for a RF board or digital board?
If it is for high-speed digital board, you would need to consider the dissipation factor (also called loss tangent) of the FR4 dielectric. When you go for even higher speeds, glass weave skew will also come affect your performance in differential channel design. In such cases, try to use mechanically spread glass.

[suleymancskn]

I would definitely recommend you to contact the manufacturer when choosing an insulator.
If you neglect this, the w and s parameters will need to be changed with the EQ file that will come before production.
You may start to violate the "distance between different tracks" rule that you pay attention to throughout the design.
You may even need to edit at some points.