Hi Graham, I was thinking about what you said trip the over-voltage detect, and looking at the schematic realized that there is no protection, i.e. ncp349. So, a small voltage variation, such as 6V, in the USB connector can brick the board?
Thanks 2015-06-19 11:21 GMT-03:00 Graham <[email protected]>: > If the BBB will run from USB power, then the BBB is probably OK. > > Put an oscilloscope on the output of the power supply that is causing the > problem, and watch what the voltage does when you turn things on. > > I had a bench power supply (B&W 1550) that when set to 5 Volts, then the > output turned on, would throw a transient up to 6 Volts then return to 5 > Volts. (The bigger the capacitor across the load, the greater the > transient.) This would trip the over-voltage detect in the BBB power > supply, which would blink the power LED once, then off after that. > > So, make sure the power supply is working properly. Some of the cheap > power supplies out there will NOT run a BBB. > > --- Graham > > == > > On Thursday, June 18, 2015 at 7:27:54 PM UTC-5, Gerald wrote: >> >> Sounds like an overvoltage condition on the 5V DC input may have damaged >> the DC input. Usually from a cheap 5V power supply. If the USB power works, >> then the rest of the board is OK. >> >> Gerald >> >> >> On Thu, Jun 18, 2015 at 11:17 AM, <[email protected]> wrote: >> >>> Hi, my Beaglebone Black have the same behavior, gives a short blink at >>> the power LED when powered. >>> But, I turned on via usb connector with power supply 5V@1A. What may >>> have happened? >>> >>> >>> Em sexta-feira, 16 de agosto de 2013 13:44:09 UTC-3, magu_ escreveu: >>>> >>>> Hi >>>> >>>> I powered the BBB over the DGND - VDD_5V. But by accident I plugged it >>>> into PWR_BUT. >>>> >>>> Now it only gives a short blink at the power LED when powered. I know >>>> this is a bad sign... But does anybody of you know if this does not mean >>>> the end of it and if it can be somehow reset? >>>> >>>> yours >>>> magu_ >>>> >>> -- >>> 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. >>> >> >> >> >> -- >> Gerald >> >> [email protected] >> http://beagleboard.org/ >> > -- > For more options, visit http://beagleboard.org/discuss > --- > You received this message because you are subscribed to a topic in the > Google Groups "BeagleBoard" group. > To unsubscribe from this topic, visit > https://groups.google.com/d/topic/beagleboard/ilf5jOwbgFE/unsubscribe. > To unsubscribe from this group and all its topics, send an email to > [email protected]. > 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.
