importer
Inactive
[on Fri 01 of Jan., 2010 14:19 EST, by rsbohn]
I bought a lipo battery from Sparkfun to use with my Maple board. When I connect it with the power jumper set to 'Battery' the blue LED flashes. Guess it came already charged. Anyway, when I change over to USB power I expect the battery lights to come on (either 'charging' or 'done'. I haven't used the battery enough to discharge it.
Do the battery lights only light up during a charge cycle, or is there a problem with my Maple board?
importer
Inactive
[on Thu 07 of Jan., 2010 19:22 EST, by poslathian]
The battery chargers have been hit and miss. We sincerely apologize for the error. Were not 100% certain, but our current understanding of the problem is this. There is no auto shutoff once the battery drops below the Vdd=3.3V necessary to keep the chip running. Thus, various board voltage dividers and leakages will continue to drain the battery all the way down to...0. When this happens, the battery charger 'protects' the battery by charging VERY slowly. We have, however, seen different behavior on production maples that used a different charging chip (since the ones from the prototype were out of stock at the time). Thus, this may or may not be the root problem, were still working on it. The charging and done lights are flakey even on boards that effectively charge the battery. Once we verify exactly what the problem is on the production maples, or discover some user servicable fix (like a trace jump) well let everyone know.
Please let us know any results you have observed while experimenting!
importer
Inactive
Charger fix found!
Another layout error, ugh...this problem didnt show up in the prototype for various reasons, but its easy to fix. See the image below! Happy charging!
By the way, if you let your battery run down too far, say...below 2.8V, the battery charger will go into safe mode and charge REALLY slowly...as in days...this is to protect the battery. You ought not let it run so low. Unfortunately, theres no switch, and power DOES drain even after Vcc drops below 3.3 and maple "turns off." An extra component will fix this issue in rev 2. So, if it seems youre out of power, pop the jumper off of battery power before it quietly drains to 0!
http://leaflabs.com/battery_charger_fix (link may be dead)
importer
Inactive
[on Wed 13 of Jan., 2010 17:25 EST, by Nic]
Eagle has done this and similar things to me once or twice, too.
In the picture, you appear to be indicating that you can jump from R23 to C11, pointing at a pin of C11 you label as ground. It looks to me like that side of C11 is VIN, not ground.
importer
Inactive
[on Wed 13 of Jan., 2010 18:07 EST, by poslathian]
ugh, you are absolutely right. My bad, better fix that diagram before someone shorts their board!
err...soo much for the jump with a piece of solder approach, a wire will still work, were working to see if its possible to scratch the soldermask off of the ground plane and jump to that
You must log in to post.