PCB design for i.MX8M

[george]

Dear all,

Now, my customer is designing the product using i.MX8M.
However, their design is held up in PCB layout.

Their product board size is larger than i.MX8M-EVK, and it needs thickness necessarily.

If considering production tolerance for board, It is difficult to fit into the rules defined in i.MX8MDQLQ Hardware Developer’s Guide.

Possibly, doesn't the rule defined in Hardware Developer’s Guide fit a board with large size or thick?

Is there any advice for the board of large size or thick?

The request specification for their board is as follows.

   180mm x 130mm（t=1.6mm）

   10-layers

Best Regards,

George

[gusarambula]

Hello George,

The Hardware Developer’s Guide recommendations apply to a board of any size. There is not a defined rule for PCB thickness per se. What matters is the required impedance which will also depend on the materials used. Manufacturers can usually help you check on that depending on the manufacturing process and materials.

If you wish to look at the i.MX8M EVK Design Files for reference you can find them on the link below.

https://www.nxp.com/webapp/Download?colCode=MCIMX8M-EVK-DESIGNFILES

I hope this helps!

Regards,

[george]

Dear gusarambula‌,

Any comment?

BR,

George

[gusarambula · Accepted solution]

Hello George,

My apologies for the delay. The manufacturer may be able to tell you the limits on how big a PCB can be done with their manufacturing process while maintaining the required impedance. If your design gets too large it may be a good idea to have a base board and a CPU board like in some EVKs, including the i.MX6 SABRE AI.

Regards,

Gustavo

[george]

Dear gusarambula,

Thank you for the reply.
Please let me know a few more.

Board thickness also becomes thick when board size is large.
And it will make manufacture within required impedance difficult.

In such a case, do you think that it should separate to a CPU board and IO board?

Best Regards,

George