Re: [beagleboard] Ddr3 length matching

2016-07-02 Thread larbi . joubala 
Ok thank you very much for the reply it is very useful.


Le jeudi 30 juin 2016 15:45:28 UTC+2, Wulf Man a écrit :
> http://referencedesigner.com/books/si/time-and-distance.php
> 
>   
> 
>   this can explain to you your issues
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>   On 6/30/2016 6:28 AM, Gerald Coley wrote:
> 
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>   
> You use the PCB SW tools to give you the lengths of
> each trace. The distance from one layer to the next is not that
> significant and is well within the needed tolerance.
> 
> 
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> 
> 
> Gerald
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> On Sat, Jun 25, 2016 at 6:16 PM, 
>   wrote:
> 
>   Hello,
> 
> 
> 
>   I am designing my own board based on the am3358 and one
> ddr3 chip. I looked at the bbb project to have a example of
> layout and i have a question about length matching for the
> ddr3 interface. How the length matching has been done if
> different layers are used? The signal on the outer layers
> doesnt travel at the same speed as the inner layers.
> 
> 
> 
> --
> 
> For more options, visit http://beagleboard.org/discuss
> 
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> 
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> 
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> -- 
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> Gerald
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>  
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> ger...@beagleboard.org
> 
> http://beagleboard.org/
> 
> gco...@emprodesign.com
> 
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>   
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>   
>   -- 
> 
>   For more options, visit http://beagleboard.org/discuss
> 
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Re: [beagleboard] Ddr3 length matching

2016-06-30 Thread evilwulfie 
http://referencedesigner.com/books/si/time-and-distance.php

this can explain to you your issues



On 6/30/2016 6:28 AM, Gerald Coley wrote:
> You use the PCB SW tools to give you the lengths of each trace. The
> distance from one layer to the next is not that significant and is
> well within the needed tolerance.
>
> Gerald
>
>
> On Sat, Jun 25, 2016 at 6:16 PM,  > wrote:
>
> Hello,
>
>   I am designing my own board based on the am3358 and one ddr3
> chip. I looked at the bbb project to have a example of layout and
> i have a question about length matching for the ddr3 interface.
> How the length matching has been done if different layers are
> used? The signal on the outer layers doesnt travel at the same
> speed as the inner layers.
>
> --
> For more options, visit http://beagleboard.org/discuss
> ---
> You received this message because you are subscribed to the Google
> Groups "BeagleBoard" group.
> To unsubscribe from this group and stop receiving emails from it,
> send an email to beagleboard+unsubscr...@googlegroups.com
> .
> To view this discussion on the web visit
> 
> https://groups.google.com/d/msgid/beagleboard/0f800b4e-6e8d-4e20-962d-7efb1d709ec2%40googlegroups.com.
> For more options, visit https://groups.google.com/d/optout.
>
>
>
>
> -- 
> Gerald
>  
> ger...@beagleboard.org 
> http://beagleboard.org/
> gcol...@emprodesign.com 
>
> -- 
> For more options, visit http://beagleboard.org/discuss
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> For more options, visit https://groups.google.com/d/optout.


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Re: [beagleboard] Ddr3 length matching

2016-06-30 Thread Gerald Coley 
You use the PCB SW tools to give you the lengths of each trace. The
distance from one layer to the next is not that significant and is well
within the needed tolerance.

Gerald


On Sat, Jun 25, 2016 at 6:16 PM,  wrote:

> Hello,
>
>   I am designing my own board based on the am3358 and one ddr3 chip. I
> looked at the bbb project to have a example of layout and i have a question
> about length matching for the ddr3 interface. How the length matching has
> been done if different layers are used? The signal on the outer layers
> doesnt travel at the same speed as the inner layers.
>
> --
> For more options, visit http://beagleboard.org/discuss
> ---
> You received this message because you are subscribed to the Google Groups
> "BeagleBoard" group.
> To unsubscribe from this group and stop receiving emails from it, send an
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> To view this discussion on the web visit
> https://groups.google.com/d/msgid/beagleboard/0f800b4e-6e8d-4e20-962d-7efb1d709ec2%40googlegroups.com
> .
> For more options, visit https://groups.google.com/d/optout.
>



-- 
Gerald

ger...@beagleboard.org
http://beagleboard.org/
gcol...@emprodesign.com

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[beagleboard] Ddr3 length matching

2016-06-30 Thread larbi . joubala 
Hello,

  I am designing my own board based on the am3358 and one ddr3 chip. I looked 
at the bbb project to have a example of layout and i have a question about 
length matching for the ddr3 interface. How the length matching has been done 
if different layers are used? The signal on the outer layers doesnt travel at 
the same speed as the inner layers.

-- 
For more options, visit http://beagleboard.org/discuss
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