Am Wed, 9 Nov 2016 21:37:52 +0100 hat "H. Nikolaus Schaller" hns@goldelico.com geschrieben:
Hi,
Good!
For me it's a disappointment as I thought that change could have been missed by the confusion of the board production being stopped.
Me too.
I had hoped it, but I didn't expect it... things have never been straightforward or easy with the Pandora or Pyra :(
Hm. Very good question! Here is a photo of the chip we have got in the newest production run:> Maybe we can read the speed from it?
Yes. According to that information it's Revision 2 of the OMAP5432, full speed, standard production run from a tray.
No prototype, even the latest revision and not limited to 1GHz.
BTW, here you can see the battery of decoupling capacitors around the OMAP. There are much less, but you also see that there are signal traces directly near them so adding more of them becomes difficult.
Hmm, from the picture it looks like there's still space on the right side of the OMAP (where there are ground planes). Also, they look like there could be smaller capacitors available as well... so we could add more.
It also looks like we could manually solder a few capacitors together and add them there... so we could do some testing here.
And doing it exactly as recommended (individual VIAs for every capacitor) is impossible. The 3 copper layers below the surface layer are for connecting the DRAM chips and there are also constraints how to route them. So we mix two set of design rules in this area.
Do we need Vias? I thought they would only be needed if the capacitors are on the other side of the PCB. Or do they need VIAs to connect to the ground plane on the other side?
Are there THAT many traces for the DRAM chips so that no vias are possible anywhere there?
The OMAP5430 would have made life much easier in this aspect - but buying RAM chips for it would have been a nightmare.
True...