Processor has gone to the happy processor graveyard in the sky and it is possible that it has take a few other chips from the board with it.
I would just buy another board and read up on voltage dividers. Gerald On Mon, Jun 6, 2016 at 3:23 PM, William Hermans <[email protected]> wrote: > By the way, you may have bolwn the PMIC I do not know much about that, but > I'm pretty sure the processor is toast. If it's a circuitco board Maybe you > should talk to Gerald to see if they can recover the board for you. However > unless you have something on the board that you absolutely have to have. > Just buy a new board. It'll be far cheaper for you that way. > > On Mon, Jun 6, 2016 at 1:18 PM, William Hermans <[email protected]> wrote: > >> >>> >>> *1. Very minor references in most BBB documentation/webpages discussing >>> Analog Inputs and max voltages. Coming from working with Pi's and >>> Arduino's, it was common to have analog inputs range from 0 to 5V, so the >>> 1.8V was unexpected.* >> >> >> Not sure where you're going on this one, but that problem is all on you. >> I'm not an EE, and even I know better than to start hooking up *ANYTHING* >> without first reading official documentation. Where the official >> documentation is the beaglebone reference manual, as well as the TRM for >> the A335x. So if you're trying to blame someone else for your screw up . . >> . well it's going to fall on deaf ears. >> >> What more, 1.8v is an absolute maximum. Meaning; you'd be lucky to not >> blow the processor if going to 1.81v. Anyway, like Harvey said above, you >> have to scale input voltages, and then that also gets scaled in software. >> >> On Mon, Jun 6, 2016 at 11:03 AM, Harvey White <[email protected]> >> wrote: >> >>> On Mon, 6 Jun 2016 10:12:43 -0700 (PDT), you wrote: >>> >>> >Hi, >>> > >>> >Yesterday I was trying to use some of the analog inputs on the BBB to >>> read >>> >my photodiode, and instead, I think I blew up the power supply on my >>> board. >>> >With power applied, I get no PWR led, so I'm pretty certain it's dead. >>> >Short of replacing the power management chip, is there anything I can >>> >do/replace to get the board working again? >>> > >>> > >>> >Brief Background >>> > >>> >I hooked up the photodiode to an Arduino and was able to read 0 - 5V >>> >easily, so I wanted to do the same on the BBB. >>> >I read some of the materials re: AIN on the BBB, but apparently I missed >>> >all the references to the max voltage of 1.8V! >>> >I started by enabling the analog inputs on the BBB, and started with >>> AIN0. >>> > >>> >With nothing attached, I was reading about 0 - so far, so good. >>> >Then I figured I'd try to see what a full 5.0V read out, so I plugged in >>> >the VDD 5V to AIN0, and all the LEDs went out instantly. >>> >Now all LEDs stay off, even the PWR LED, when power is applied. >>> > >>> >No doubt, it was stupid, but I have a few additional takeaways - >>> >1. Very minor references in most BBB documentation/webpages discussing >>> >Analog Inputs and max voltages. >>> >Coming from working with Pi's and Arduino's, it was common to have >>> analog >>> >inputs range from 0 to 5V, so the 1.8V was unexpected. >>> >>> Actually, it's 0 to VCC on the MEGA and XMEGA chips. The Mega chips >>> can run at 3.3 volts, and the XMEGA chips *must* run at no more than >>> 3.3 volts. >>> >>> > >>> >2. Isn't there any protection at all from this kind of damage? Or was >>> the >>> >main problem that I used the VDD 5V and fed it into the AIN0 port? >>> >>> These are generally direct chip inputs, and there's generally no >>> buffering. >>> >>> >Would I have killed it if I used the VDD ADC instead of the VDD 5v or >>> would >>> >using the VCC ADC possibly have protected it? >>> >>> 1.8 volts maximum. >>> >>> > >>> >3. What is the "normal" way of using the BBB analog inputs with 5V >>> levels? >>> > Is it possible - or is there where I would use a level-shifter or zener >>> >diode? >>> >>> Level shifters are generally digital, and zener diodes don't help all >>> that much (and are not really a good idea here). My standard advice >>> would be to run the analog voltage through a non-inverting op amp >>> configured as a gain stage. You run the op-amp (and have to pick one >>> that does rail to rail and also runs from 1.8 volts) from the 1.8 volt >>> supply. >>> >>> Harvey >>> >>> > >>> >Thanks for the any comments or additional info provided! >>> >>> >>> -- >>> 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]. >>> To view this discussion on the web visit >>> https://groups.google.com/d/msgid/beagleboard/hbeblb1809orgk011t8crt9ucj3m942qlm%404ax.com >>> . >>> 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]. > To view this discussion on the web visit > https://groups.google.com/d/msgid/beagleboard/CALHSORqsExf6K0ZTPDECvj4mhL2nFYzY%3D6gnAe2fv38hZSgB1A%40mail.gmail.com > <https://groups.google.com/d/msgid/beagleboard/CALHSORqsExf6K0ZTPDECvj4mhL2nFYzY%3D6gnAe2fv38hZSgB1A%40mail.gmail.com?utm_medium=email&utm_source=footer> > . > > For more options, visit https://groups.google.com/d/optout. > -- Gerald [email protected] http://beagleboard.org/ [email protected] -- 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]. To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/CAHK_S%2Be%2BNhSnYwv6kDQ-b4q157MH%3DJCgA2f9S0ehv_pcVdTjfw%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
