[HW] 12V Power -> Smoke on TPS2141

Hi !

  I just got my brand new beagle,
  1) I took my router power supply (12V) and plug it in, i see LEDS on
  2) I made a serial cable
  3) Plug the board to a 5V power supply
  4) Watch the smoke coming out TPS2141

  I have ordered some samples from TI to replace TPS2141, i also have
check in the schematics that 5V line is attached to TWL4030 VBUS
signal (USB) I hope did not get the thing broken.

  First, i guess i have no warranty for such incident. Am i right?
  Second, it would be useful for next revision of the board if you can
add a protection on Voltage Input, it won't increase much our budget,
i wouldn't mind to pay an extra buck and have not broken the board.

Kind Regards

So, as to protection, exactly how much voltage should it tolerate? 110VAC, 220VAC, 24VDC, etc. Can you provide a limit that you think will be acceptable? Any changes won’t be made before the next revision which is after the next 7000 boards. The other question is the cost. We have worked to keep the cost down and anything we add will add cost. We have shipped 5000 boards and this is only the second instance of someone plugging in 12V to the board. It is hard to justify the added cost based on two people.

If the board can be repaired it will be repaired free of charge. Just request an RMA.

Gerald

Hi Gerald,

So, as to protection, exactly how much voltage should it tolerate? 110VAC,
220VAC, 24VDC, etc. Can you provide a limit that you think will be
acceptable?

At least in my country common voltages of power supplies for consumer
electronics, with the size of the input power connector on the
beagleboard, are up to 12Vdc. So my wish is that beagleboard can be
protected up to twice that voltage, so 24Vdc would be my first
approximation.

If the board can be repaired it will be repaired free of charge. Just
request an RMA.

I took off the TPS2141 device, so they won't take the board. :-/
I'll need to expend twice the money I already expend having to order
another board.

Thanks for taking this into account.

Kind Regards,

You should have gone the RMA route before taking the part off and been honest up front with what you had done. I would have had them send you a replacement board where the total cost to you would have only been time.

Gerald

Thinking of it:
some protection or tolerance would be nice as people need to provide
their own power brick and not all bricks are equally good so there is
always a chance that even with a brick labeled 5v there will be e.g.
5.2 v on the output. (and frankly speaking I just grabbed a 5v brick I
had lying around without really measuring the voltage)
I can also imagine publishing a small circuit that people can build
themselves to add protection, to deal e.g. with voltage fluctuations.

The other easily made error is using a brick with + and - reversed
(although maybe having + as center is the common scenario, not sure
about that).

Frans

I would not expect a devel board to be very tolerant about voltage but I would appreciate the beagle to be tolerant to an unregulated PSU if that would not add to much to the cost.

/Arne

I will take all your inputs into consideration for the next version after the next version. We have already spun the board again for REV C3 for some minor fixes and 5000 boards are on order. So it will be a while before this issue can be addressed.

Gerald.

Oops, I think you messed up by mentioning a REV C3, as the obvious questions will be, what problems does the REV C3 board fix, and are the boards released March 31st, REV C2 or REV C3? If they are REV C2, when will you release the REV C3 boards?

Regards,

We added ground to the mounting holes and made them plated through. So, for those who are waiting for that feature, those will start shipping in late May or early June.

Gerald

Hi Gerald,

You should have gone the RMA route before taking the part off and been
honest up front with what you had done. I would have had them send you a
replacement board where the total cost to you would have only been time.

I did went through RMA, but after taking the part off. I have even be
honest to them telling that I took off the part, that is why I was
telling you, that a replacement was not posible. But, likely you are
proposing a deal, it would be OK if I get one board and you send me
two? I'll give my board back to SAT so they can fixe it or do what
ever they think. I still have hope processor is fine as I can heard
the burst audio tone and LED on.

Anycase, taking into account my voltage protection proposal it's been
more that what I expected, so /me nods you. Additionally i would
propose you to do a challenge among beagle community and see who is
the hacker that provides the most inexpensive efficient voltage
protection design for beagle board, which I would be glad to
contribute.

Kind regards,
  Héctor Orón

I control the RMA team. I would have had them send you a replacement. I will not send you two boards. If you return the board as is, I will have them send you a replacement board upon receipt of the board you have.

Gerald

Hi, There,

It has been reported that the USB bugs(HOST & EHCI) have been fixed up in Version C2 of beagleboard?
I wonder if there introduced some kind of new chips or just the improvement of TPS65930 driver?

Thanks for the reply

Liu Enn

Thanks Gerald, that's very kind. I'll send you my board to get a
replacement and i'll get another board from digikey too.

Wait to order the second board for a week or so. We are shipping out Rev C2 boards the end of the week to D/K. I don’t exactly know when they will make them available, but at least you know that they have them in stock whne you order them.

Gerald

The TPS65930 is not used on the EHCI port. The TWL4030 is used on the OTG port. The EHCI port uses the SMSC USB3322…

Gerald

2009/3/17 liuez <liuez@embedinfo.com>

Hector Oron <hector.oron@gmail.com> writes:

Anycase, taking into account my voltage protection proposal it's been
more that what I expected, so /me nods you. Additionally i would
propose you to do a challenge among beagle community and see who is
the hacker that provides the most inexpensive efficient voltage
protection design for beagle board, which I would be glad to
contribute.

Here's my idea: http://thrashbarg.mansr.com/~mru/beagle_overvoltage.jpg

Do have a datasheet and a cost?

Gerald

2009/3/17 Måns Rullgård <mans@mansr.com>

Someone would still manage to fry the Beagleboard.

David.

davidcb <n2vdy@yahoo.com> writes:

Yeah, I knew that was coming. hehehe
So now we know how the BGAs get soldered.

David.