Very true. So I guess even just using a li-po or li-ion on the bone would be much easier.
-Wil On Nov 5, 2013 11:59 PM, "Brandon I" <[email protected]> wrote: > > A cap big enough should be able to handle that. > > Not sure if I did my math right, but for 2 seconds at 2W (beaglebone will > be booting), and assuming his 24V to 5V regulator can regulate with an > input voltage all the way down to 12V, that's around 20mF. I guess that's > doable with $$$. > > It wouldn't be as simple as connecting the cap to the accessories line, > since this would absolutely destroy your relay contacts from the inrush in > charging this gigantic cap from 0V. And, you would have to throw a diode in > so you didn't power *all* of your accessories with this cap. > > > On Tue, Nov 5, 2013 at 9:15 PM, Wilfredo Nieves > <[email protected]>wrote: > >> Not necessarily , my car is a 95 3kgt and it starts within 1-2 seconds of >> turning it over. A cap big enough should be able to handle that. As for the >> 24v idk how I didn't catch that, but then again who knows it is possible. >> >> -Wil >> On Nov 5, 2013 9:30 PM, "Brandon I" <[email protected]> wrote: >> >>> > I've connected beagleboneblack to my car power supply with 24V to 5V >>> step down. >>> >>> 24V "power supply" in a car? If this means you're this from the >>> accessories circuit, you're doomed. Accessories are turned off while the >>> car is being started, and a cap won't be enough to power the beaglebone, >>> since they stay off as long as you're turning the engine. Another problem >>> is, you'll corrupt the filesystem with an out-of-the-box beaglebone. You'll >>> *have to* use a read only file system. >>> >>> You could tie the beaglebone directly to the battery (with a fuse of >>> course) and use some circuit to monitor when to turn it on and off. >>> >>> On Tuesday, November 5, 2013 9:24:49 AM UTC-8, Wilfredo Nieves wrote: >>>> >>>> I think you should be fine as long as you don't use a value that is too >>>> high or too low. Too high may cause problems with rise time and too low may >>>> not keep enough power supplied for the board to stay powered up. Also caps >>>> aren't like batteries, the charge almost instantaneously where as batteries >>>> need time to fully charge so as long as you can get the cap charged fast >>>> enough the board should power up without any problems. >>>> >>>> -Wil >>>> On Nov 5, 2013 8:27 AM, "satya gowtham kudupudi" <[email protected]> >>>> wrote: >>>> >>>>> Thank you. I will give a try. As per the post here >>>>> https://groups.google.com/forum/#!msg/beagleboard/ >>>>> aXv6An1xfqI/mURD3LfQ5dMJ? the power source should have proper rise >>>>> time. I'm afraid a capacitor will increase the rise time. Any way I'll >>>>> give >>>>> a try. >>>>> >>>>> -- >>>>> 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/groups/opt_out. >>>>> >>>> -- >>> 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/groups/opt_out. >>> >> -- >> 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/5toeq-9pcfU/unsubscribe. >> To unsubscribe from this group and all its topics, send an email to >> [email protected]. >> For more options, visit https://groups.google.com/groups/opt_out. >> > > -- > 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/groups/opt_out. > -- 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/groups/opt_out.
