i.MX ProcessorsのトピックRe: iMX53 PCB impedance control

iMX53 PCB impedance control

kamejoko80 — Fri, 07 Sep 2012 19:22:48 GMT

Hi all, I wan to reuse the iMX53 QSB-R PCB stack up in oder to design a new custome board, but I don't known detail of the stack up such as PCB thickness and the dielectric thickness for each layer... I saw there are some different point between the allegro PCB design board stackup and the detail information from their gerber files. Which is correct that I should follow and ask the PCB manufacturer for PCB impedance controlling? Any suggestions ? Best regard

Re: iMX53 PCB impedance control

NicolasIzquierd — Fri, 07 Sep 2012 20:17:18 GMT

Hi Phuong

As you mention, Inside the Gerbers Files and the Layout file as well, there is a table named "IMPEDANCE REQUIREMENTS" together with the PCB Material and the weigh of copper for each layer from the StackUp, you should with your PCB Manufacturer agreed in to match as close as possible to get these impedance in your traces, and define the proper thickness of you pcb.

hope this can help you.

-ni

Re: iMX53 PCB impedance control

JorgeRama_rezRi — Fri, 07 Sep 2012 20:24:06 GMT

Hi Minh,

The MX53 QSB-R PCB is compliant with IPC-A-600 Class 2, this standard specifies board thickness. The stackup of the board, which specifies the layer thickness, is included in the layout. I'm attaching a PDF of the stackup and fab notes, these include everything you need. Unfortunately, I don't have the IPC-A-600 document, but this is something your manufacturer must know, so they can provide some guidance about it.

Best regards.

Jorge.

Re: iMX53 PCB impedance control

TheAdmiral — Fri, 07 Sep 2012 20:41:02 GMT

Hi Minh,

Always follow the recommendations fo the PCB manufacturer. Each manufacturer has a different process and different set of materials. And the materials used may vary depending on what the manufacturer has on hand. Give the manufacturer some tartget values for: overall thickness, number of layers, and desired trace impedances. Ask them to provide to you a recommended board stack up and trace thicknesses. Then use these in your design. The initial stackup information provided by the manufacturer for the Freescale QuickStart board is contained in chapter 8 of the Hardware Reference Manual for i.MX53 Quick Start (available for download from Freescale).

Cheers.