Basically what happens is that the board that i am designing has a general purpose port for external sensor boards. It has 6 inputs for analog signals and 8 for some general gpios plus i2C lines (and also suppply lines among witch a 1.8V). On the board that i am designing i am using the 1.8V supply to power two MEMS ( which i know ho much they consume) and the protection circuits that i mentioned earlier to limit the analog input to 1.8V consists of two diodes and an RC filter, so i am guessing not much current will be lost in those, nothing significant anyway (correct me if i am wrong).
As for the consumption on the external sensors that may be hooked up it depends on the application so i do not know exactly how much that will draw. Regards, Cristian 2014-07-05 19:56 GMT+02:00 John Syn <[email protected]>: > > From: Cristian Mitu <[email protected]> > Reply-To: "[email protected]" <[email protected]> > Date: Saturday, July 5, 2014 at 3:17 AM > To: "[email protected]" <[email protected]> > Subject: Re: [beagleboard] Analog voltage referance pin > > How much current should the LDO be able to carry considering that i am > using BBB. > > Not sure how to answer that because it depends on what circuit you are > adding. Read the BBB SRM which defines how much current you can draw from > the 5V pins on the P9 connector. Given that your circuit is related to the > ADC, I cannot imagine that you would need more that 250mA so most LDO will > work for your requirement. Remember to use proper supply decoupling and > filtering because any noise on the ADC circuits will cause your > measurements to be inconsistent. > > Regards, > John > > > > Regards, > Cristian > > > 2014-07-05 4:02 GMT+02:00 John Syn <[email protected]>: > >> >> From: Cristian Mitu <[email protected]> >> Reply-To: "[email protected]" <[email protected]> >> Date: Friday, July 4, 2014 at 2:38 PM >> To: "[email protected]" <[email protected]> >> Subject: [beagleboard] Analog voltage referance pin >> >> Hello guys, >> >> >> I have noticed that my BeagleBoneBlack has a VDD_ADC that is supposed to >> be a 1.8V reference voltage. On the board that i am making i have some >> components that need 1.8V(among which some simple protection circuits for >> the Analog inputs). I was thinking that instead of using an LOD for >> conversion i could draw directly from that pin to power those components. >> Is this a viable solution or is there a problem or drawback if i use the >> 1.8V reference voltage pin ? Thank you in advance for your responses. >> >> It is a reference pin, not a power pin, so no you cannot draw current for >> your other circuits. A small LDO regulator is inexpensive so just add one. >> >> Regards, >> John >> >> >> -- >> 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. >> >> -- >> 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/CCsy0Sc5UjQ/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. > > -- > 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/CCsy0Sc5UjQ/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.
