I measure 3.3V on P9.3. 

USB powering shows the 'good' powercycle, 5V via P9.5 shows a 'bad' 
powercycle. 

Btw, I seen that in revision A6 and A4 there is an NCP349 chip between 
VDD_5V and pin 10 of the TPS65217b, which I cant see in revision A5.


On Thursday, March 20, 2014 2:52:43 PM UTC+1, Gerald wrote:
>
> Where are you looking exactly?
>
> Gerald
>
>
>
> On Thu, Mar 20, 2014 at 8:51 AM, Kees k <[email protected]<javascript:>
> > wrote:
>
>>
>>
>> The 5V is fine (maybe a little spike of 0.8V after 60 ms PS).
>>
>> However, the 3.3V gives a strange 2-stage powerup cycle. I compared a 
>> revision A5C to a revision A6, see plots below. 
>>
>> As can be seen the A5C has a 'normal ' powerup cycle on the 3.3V, but the 
>> A6 a 2-stage powerup cycle. May this cause any problems with PHY?
>>
>>
>>
>>
>> <https://lh6.googleusercontent.com/-oYQffwcsuTE/Uyrx4haRJUI/AAAAAAAACC8/cW3xQual_Q8/s1600/20140320_143534.jpg>
>>
>>
>> <https://lh3.googleusercontent.com/-_veLX8dOp6w/Uyrx2A6EsRI/AAAAAAAACC0/fOMrXaeqSfE/s1600/20140320_142321.jpg>
>>
>>
>> On Thursday, March 20, 2014 2:44:33 PM UTC+1, [email protected] wrote:
>>>
>>> Robert Nelson <[email protected]> wrote: 
>>> > On Thu, Mar 20, 2014 at 4:48 AM, Kees k <[email protected]> 
>>> > wrote: 
>>> > > I have seen this problem repeatedly by A6 revision hardware, but not 
>>> with 
>>> > > revision A5C hardware (I am running exactly the same software on 
>>> both). 
>>> > > 
>>> > > Noteworthy is that the "PHY problem" only appears when powering the 
>>> BBB via 
>>> > > the headers. Powering via USB does not give any problems. 
>>> > 
>>> > Well, if it works via USB, but not with the headers. (I didn't check 
>>> > if the Ethernet can be powered from the headers.) 
>>> > 
>>> I'm powering my BBB using P9 pins 1/2 for 0v and 5/6 for +5v, I'm 
>>> using the 'real' ethernet connection and it works fine.  It has run 
>>> with no problems for at least 24 hours, staying connected (ssh) to my 
>>> desktop computer. 
>>>
>>> -- 
>>> Chris Green 
>>> ยท 
>>>
>>>  -- 
>> 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 [email protected] <javascript:>.
>> For more options, visit https://groups.google.com/d/optout.
>>
>
>

-- 
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 [email protected].
For more options, visit https://groups.google.com/d/optout.

Reply via email to