Hi! Did ever someone use a so called Powerbank, an extended iphone battery and charger. Prices start at 10$ (maybe only for th BBW, because only 1A) but there are items available with more amps, see e.g. this one: http://www.ebay.com/itm/20000-mAh-External-Portable-Powerbank-Power-Bank-Source-For-Samsung-i9300-/300963778955?pt=US_Cell_Phone_PDA_Batteries&hash=item4612d6d18b
They claim 20Ah and 2.1A for 21$. Dieter On Wed, Nov 13, 2013 at 5:43 PM, Mike Bremford <m...@bfo.co.uk> wrote: > Search ebay for "LM2596 buck converter". Variable output up to 3A, 10 for > $10 from China. I'm running my setup from a 12V car battery through these. > There are buck/boost converters to be had on ebay too, they're a bit more > expensive but still probably cheaper than you can make them yourself. > > > On 13 November 2013 15:03, <rowland.oflahe...@gmail.com> wrote: >> >> I agreed there are better solutions available and that is really what I am >> asking... what are those better solutions? For what I am looking to do is >> having everything needed to run the BBB off battery for as cheap as >> possible. We are designing a hardware setup for students to use and they >> have to be able to buy all the components for as cheap as possible. The >> problem with Lipo (from what I have seen) is that the chargers are the >> expensive part. >> >> Here is where I am at right now. Need at least 9V for running motors as >> well as the BBB. >> 3-cell Lipo = $9 from HobbyKing >> Lipo charger = $12 from HobbyKing >> Lipo charger power supply = $8 from Amazon >> Voltage Reg, diode, caps, wires etc. = $3 from DigitKey >> >> This might be the best solution. But my thought was students might already >> have AA battery chargers at home. >> >> Thoughts? >> >> Also, can you point me to a better circuit design that doesn't use the >> 7805? >> >> -Rowland >> >> >> On Monday, November 11, 2013 4:22:39 PM UTC-5, Dieter Wirz wrote: >>> >>> Ron is perfectly right! >>> And where do you get cheap rechargeable batteries? >>> LIPO prices are going down >>> alcaline prices are going up >>> >>> Do you really want to invest time and money in last millennium >>> alcaline technology? >>> >>> 7805? If you connect 9v to an 7805 about 40% of the power is converted >>> to heat. There are much better solutions available. >>> >>> BTW @Ron: What buck/boost regulators are you using. Maybe you can >>> provide some hints to the community... I have the ADP1111 sitting on >>> my Desktop, but I did not find the time to solder something >>> together..... >> >> -- >> 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 beagleboard+unsubscr...@googlegroups.com. >> 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 beagleboard+unsubscr...@googlegroups.com. > 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 beagleboard+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
