anyone know of a DC/DC converter with 5v USB out?

[theRealFury]

Basically im looking for a small unit that i can hardwire into my pack which is 12s lipo so 40-50v tolerances. that has a 5v USB output (minimum 500ma) so that i can plug my android phone in while i ride as i use it for GPS and data logging.

I bought one of those cheap 110/220v USB plugs that you can plug into your wall hoping that they would run on DC, but unfortunately they either do not run on DC at all or not at the voltage of my pack. Does any of you guys have a unit that acomplishes this or any tips on how to go about doing this?

 

[ZOMGVTEK]

Your android handset might charge simply off a 5V power source, which should be very easy to make. Theres many options for voltage regulators in that input range, and 5V is easy to achieve. For example, the Lyen DC-DC converter would do exactly what you want. If your device will charge off a 5V 'dumb' power source, all you need to do is get/pull a female USB socket and run 5V into it.

http://endless-sphere.com/forums/viewtopic.php?f=31&t=21459&hilit=converter
Theres quite a few reg's that will do this as well, at a lower cost, but this is 'easy'.

12S is far too low voltage to start running standard 120AC stuff off. The majority of switching supply based stuff will run off 24S, but thats twice the voltage. Its only really done since its extremely rare to find a regulator that will take 100V down to something useable.

 

[Sacman]

I found these 2 on eBay.

DC/DC Converter WPC10R48S05P 28-75V In,5V @2A Out 3pcs
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=370182211916&ssPageName=STRK:MEWAX:IT

1 DC/DC Converter WPC10R48S05P 48V In, 5V @ 2A Out
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=220388513048&ssPageName=STRK:MEWAX:IT

 

[theRealFury]

Thanks for the replies guys, ill look into getting a DC/DC converter and feeding the power into a USB connector. I guess i was kinda hoping that there was a unit already built with a USB connection for the output but i have been unable to find one. I just dont really trust my electronics skills enough to be able to happily plug a $800 phone into something i bodged together .

At the moment though i guess thats the only option. Just need to find out if my phone can handle a 'dumb' 5v supply or if its too 'smart' for that :lol:

 

[Sacman]

I too was planning to mount and wire up my iPhone on my ebikes so I can use the Map and GPS. And I'm running 12s lipos too.
I already got the DC/DC converter and USB adapter plug. Now I just need to wire it up.

 

[Arc EV Racing]

We have a Nokia mobile phone charger installed on the race bike to supply 5v to the BMS. We're running 25s LiPo but when I was first testing the idea (thanks Steve) I ran it on a 48V DC bench supply. Output was slightly out of spec at something like 5.5V (it was 5V when running on AC), and output voltage seemed to rise slightly as input voltage fell. We cracked off the case and soldered input wires direct the the board, then fashioned an enclosure out of multiple layers of heatshrink. Works a treat.

I used a 240VAC charger btw