Hey guys,
Can anyone suggest an IC that could be used to charge dual cell Lipo batteries (7.4V) with cell balancing? Ideally the IC would be powerful enough that it could charge even if the system is under a light load. I am looking for something similar to
the MAX 1555 IC (http://www.sparkfun.com/products/674) but for multiple cells. My google search has been fruitless - I must be using the wrong keywords. Thanks for any help!
PS I am not looking for a full charging system! I already have one. Instead I am trying to build one and was wondering if any IC other than a micro-controller exists to charge Lipos safely. Also don't suggesting trickle charging as it doesn't work with Lipos.
I had the same idea earlier
I had the same idea earlier today (technically yesterday I suppose). I have not found an IC for it and would find it odd that no one like Sparkfun, Seeedstudio, or Adafruit sells a dual charger if it does exist like the common single cell ones.
Hat Trick
Wow, its a three-fer today! Hooray!
I have nothing to add but I want one too. I suppose the logical thing here would be to try to expand this conversation. I will shoot Red Box an email and you’re down with Adafruit, Pat. Oh, I guess we will see them soon.
Word.
Microcontroller…
"…if any IC exists that is not a microcontroller…"
Hmmm… Why could it not be a micro controller? This is screaming picaxe 08m2 to me.
We gotta figure out how the charge cycle works and what this whole balancing thing is. I would think at it’s core, we are talking some ADC’s for volt and/or current monitoring, and an output or two going to some kinda power-transisor. Man, there has to be a nerd somewhere who has been waiting his whole life to explain this to us.
Yeah but there are already
Yeah but there are already little tiny IC’s that already have this all figured out that cost only a dollar or two, such as the MAX1555 for single cell batteries. I mean, you can take alot of effort trying to figure it out, but why not just spend a dollar?
Found the IC, a MAX1640,
Found the IC, a MAX1640, capable of charging LI-Ion, Li Poly, NIMH and NICAD batteries, anywhere from 2-16 cells, and 1-6 lipo cells
http://www.maxim-ic.com/datasheet/index.mvp/id/1751
And i have some floating around! BREAKOUT BOARDS!
I think the MCP73213 is the
I think the MCP73213 is the chip to use, its dead simple to use:
Cheap, 10 pins too.
Beautiful. I am waiting for
Beautiful. I am waiting for a board to buy from you…
Thanks for the great replies
Thanks for the great replies everyone! This is why LMR is so great. Last night I had an issue, tonight I have feedback from 5 talented people to solve it!
Expect it as soon as I can
Expect it as soon as I can find a 10 lead QFN package!
Krumlink once again you have
Krumlink once again you have proven yourself to be the IC guru! This is exactly the type of chip I was looking for. It’s even simpler than I expected it to be! Thank you very much!
I just prowl through stacks
I just prowl through stacks of datasheets via the internets… Its what I do hehe 
@sample order-ers
Just wanted to get a list of what you guys got as your samples. I know last night a few of us did the free sample rounds and I was curious as to what you guys got a hold of. I was going to do some sample ordering myself today and wanted to not only get some of the same stuff you guys got (so I could replicate your experiments on my end) but also some chips you guys didn’t get so we can all try different things and then compare results.
That’s it --What did you get? and where did you get it from?
I got some MCP73213’s and
I got some MCP73213’s and some PIC18F6722, which is a 64 pin beast, its a good step up from a 40 pin PIC but less intimidating than a 80 pin pic.
Keepin’ it simple
2 MCP73213.
i would seriously recommend
i would seriously recommend against dual charging any lithium-ion based cells.
the likelyhood of a disastrous failure increases quite allot when you do.
and keep in mind, these things can explode if you charge them wrong.
i would seriously recommend
oops, double post…
Board is in progress, I had
Board is in progress, I had to make my own DFN10 package, not as big as a pain in the ass as I thought it would be.