topic Re: i.mx6 board stack up in i.MX Processors

i.mx6 board stack up

douglasbolton — Thu, 14 Feb 2013 01:59:00 GMT

My PCB fabricator is having trouble achieving the same impedance control used for the i.mx6 SD reference design stackup -

Layer1 = 1/2 oz to 1 oz

Layer2 = 1 oz

Layer3 = 1/2 oz

Layer4 = 1 oz

Layer5 = 1 oz

Layer6 = 1/2 oz

Layer7 = 1 oz

Layer8 = 1/2 oz to 1 oz

Impedance control Single

50R Layer1/Layer8 = 4.7 mil

50R Layer3/Layer6 = 4.5 mil

Impedance Control Differential

90R Layer1/Layer2/Layer3/Layer4 = 5.3/3.7 mil

100R Layer1/Layer8 = 3.7/5.3 mil

100R Layer3/Layer6 = 3.8/5.2 mil

Does anyone have PCB fabrication details (dielectric thickness etc) using the parameters above.

Thanks

Doug.

Re: i.mx6 board stack up

douglasbolton — Sat, 16 Feb 2013 07:23:08 GMT

Sorry, slight correction to the impedance layers-

Layer1 = 1/2 oz to 1 oz

Layer2 = 1 oz

Layer3 = 1/2 oz

Layer4 = 1 oz

Layer5 = 1 oz

Layer6 = 1/2 oz

Layer7 = 1 oz

Layer8 = 1/2 oz to 1 oz

Impedance control Single

50R Layer1/Layer8 = 4.7 mil

50R Layer3/Layer6 = 4.5 mil

Impedance Control Differential

90R Layer1/Layer8 = 5.3/3.7 mil

100R Layer1/Layer8 = 3.7/5.3 mil

100R Layer3/Layer6 = 3.8/5.2 mil

Re: i.mx6 board stack up

JorgeRama_rezRi — Mon, 18 Feb 2013 23:07:29 GMT

Hi Douglas,

Please find attached the dielectric thickness data of our SDP, which uses the same characteristics you mentioned. Please let me know if you need any other data.

Best regards.

Jorge.

Re: i.mx6 board stack up

douglasbolton — Mon, 18 Feb 2013 23:36:18 GMT

Thank you Jorge.

I am just concerned that the stack up table (dielectric etc) uses different copper weights than those in the first part of the document and also on the gerbers -

Your attached table =

3/8 oz copper

1/2 oz copper

3/8 oz copper

Gerbers =

Layer1 = 1/2 oz to 1 oz

Layer2 = 1 oz

Layer3 = 1/2 oz

Layer4 = 1 oz

Layer5 = 1 oz

Layer6 = 1/2 oz

Layer7 = 1 oz

Layer8 = 1/2 oz to 1 oz

Which copper weights are correct for the Freescale SD board ?

Thanks

Doug.

Re: i.mx6 board stack up

JorgeRama_rezRi — Wed, 20 Feb 2013 23:31:18 GMT

Hi Doug,

Didn't notice that. Let me confirm and I'll get back to you asap.

Best regards.

Jorge.

Re: i.mx6 board stack up

YixingKong — Mon, 25 Feb 2013 06:27:03 GMT

Hi Dong,

Has JorgeRama_rezRivero answered you?

Re: i.mx6 board stack up

douglasbolton — Mon, 25 Feb 2013 06:48:16 GMT

No I haven't had an answer yet.

Regards

Doug.

Re: i.mx6 board stack up

JorgeRama_rezRi — Mon, 25 Feb 2013 23:10:26 GMT

Hi Doug,

I've sent an e-mail to the guys in charge of the manufacture to check the actual numbers. I'll let you know the answer asap.

Best regards.

Jorge.

Re: i.mx6 board stack up

JorgeRama_rezRi — Tue, 26 Feb 2013 22:41:59 GMT

Hi Doug,

Please find attached the actual numbers with wich the board was manufactured.

Best regards.

Jorge.

Re: i.mx6 board stack up

douglasbolton — Tue, 26 Feb 2013 23:52:56 GMT

Hi Jorge,

Thank you for the information.

I still have some doubts.

In the gerber files the differential track width/spacing/width's are -

90R = 5.3/3.7/5.3

100R = 3.7/5.3/3.7 & 3.8/5.2/3.8

In the spreadsheet you sent the differential track width/spacing/width's are -

90R = 5.3/9/5.3

100R = 3.7/9/3.7 & 3.8/9/3.8

Also in the spreadsheet the internal layer copper thicknesses are all the same (1.3mils). The gerber file fabrication notes have different copper thicknesses for the internal layers.

I may be reading this wrongly but I still don't think this spreadsheet matches the gerber fabrication notes or differential tracks.

Thanks again for your help.

Doug.

Re: i.mx6 board stack up

marksiggins — Fri, 21 Jun 2013 11:01:48 GMT

Hi Jorge.

Did this ever come to a conclusion? I need the same information, as I am about to start layout of an iMX6 design, and the gerber notes, the word document, and that spreadsheet, all conflict with each other.

Can you tell us please, which is correct?

Best regards,

Mark.

Re: i.mx6 board stack up

noeliascotti — Thu, 13 Feb 2014 18:44:48 GMT

Hi,

I'm defining the stackup for my iMX6 board and I'm confused because the Freescale info is a mess.

Does anyone have the correct info?

Thanks,

Noelia

Re: i.mx6 board stack up

Richard1z — Fri, 21 Aug 2015 11:33:26 GMT

Hi Doug,

did you ever get a successful conclusion on this ?

I'm facing the same problems with the the Freescale documentation inconsistencies while designing an iMX6D/Q board.

Richard.