Seriously, a battery (for the most part) can supply a few times it's current capacity. Like anything, there are exceptions, and in this case that exception are 9V "transistor" batteries (the square ones). These are generally low current batteries. But, other than that, you can just hook up a set of batteries to the Vin. Five AAs would be fine, or plan for about 7.5 or so. You don't need to do anything special to supply 250 ma: the board will draw what it needs (or it it's too much for the battery, it will draw as much as it can and then drop the voltage).
Thanks, so (if I understand correctly) I'll supply 7.5V and (just to pick a number) if I get 2000ma/AA cell then I'll have 10,000 ma so I should run for ... 40 hours or so?
I guess a more realistic output would be about 1000ma/AA cell. If I connect the batteries to Vin, do I treat it just as if I were powering from Vdd? Can I power from both Vdd (via a 9V) and also Vin (5-6 AA)?
OK, I think I have it...a bit... The stamp regulates the Vin to +5V and it appears on the Vdd so the Vin only connects to the AA batteries. Then i proceed as usual but I can draw 250ma as long as the AA batteries hold out.
Comments
Seriously, a battery (for the most part) can supply a few times it's current capacity. Like anything, there are exceptions, and in this case that exception are 9V "transistor" batteries (the square ones). These are generally low current batteries. But, other than that, you can just hook up a set of batteries to the Vin. Five AAs would be fine, or plan for about 7.5 or so. You don't need to do anything special to supply 250 ma: the board will draw what it needs (or it it's too much for the battery, it will draw as much as it can and then drop the voltage).
Thank you very much