IanCanada's Latest RPi GB Goodies Impressions... and your tweaks, mods and hints...

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Back pedalling a bit here but it seems I haven't had my 3 rails of 3v3 correct on the dual dac. I fed the 3 rails separately but that is it... performed no other mods.
So my 3 rails are still 'commoned'.

I think I understand from reading the manual that removing the small daughter boards breaks the links and does give us 3 separate rails?

I also read here somewhere about keeping the daughter boards but instead cutting some tracks. I am struggling to see these tracks. Does anyone have a picture?

Regards
James
 
Back pedalling a bit here but it seems I haven't had my 3 rails of 3v3 correct on the dual dac. I fed the 3 rails separately but that is it... performed no other mods.
So my 3 rails are still 'commoned'.

I think I understand from reading the manual that removing the small daughter boards breaks the links and does give us 3 separate rails?

I also read here somewhere about keeping the daughter boards but instead cutting some tracks. I am struggling to see these tracks. Does anyone have a picture?

Regards
James

See jacklee's post at #182 of this thread.
 
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Thanks for all the help thus far and apologies for being a bit green with this. I really dont wish to screw up this DAC.

So I have sussed out the 'IN' trace on the underside. It is surrounded by the ground plane so I would need to make sure I dont create a short where I cut....make sure it's a clean gap between the two .

So should I cut the traces where I have marked. That will isolate the 3 power rails from each other?

Thanks again
 

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Is that not the incoming + rail (that connected to the + power terminal)?
I don't think you need to cut this. If you have 3 external battery 3V3 rails none will connect to this rail anyway. If you have 3 local 3V3 regulators these will need power (+5V) from this rail.
Also this rail is not broken by removing the daughterboards.....
 
So should I cut the traces where I have marked.

Thanks again

NO.

Are you trying to feed 3 x 3.3 V rails to the DAC ?

If so you cut from the other other side of the board, there are 3 bridges between mother and daughter board these have the tracks under the mask.

You can fit 2 pin connectors if you file the pins down a little.

An externally hosted image should be here but it was not working when we last tested it.



Cut the one's marked 'IN'.

Then feed +Ve to the daughter board 'in' and ground to either ground pin. This leaves the caps connected.
 
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I had a request to share the information on cutting the 3v3 rails clearly as Simon had helped me with via PM so here I share an image.
Hopefully this helps others that are less adept at all this much like myself.

And to quote

"Cut the in track where it bridges the gap between main and daughter boards. On mine I cut two for external regs and supercapped the 3rd which remains uncut. Leave the underside as is, no need to cut that, then you can undo any cut by bridging with wire on top if required"
 

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