On Mon, Oct 17, 2011 at 10:01 PM, V G wrote: > You probably won't charge the NiMH batteries fully. Also, NiMH shouldn't = be > charged with a constant-voltage method. You charge them with constant > current, and detect a -dV and/or +dt (rise in temperature). Also, > personally, I don't feel comfortable charging them in series like that si= nce > slight differences in capacities might cause odd charging behavior over > time. I always charge in parallel, via single channels. Also note that yo= u > don't know exactly how much current is going through the transistor since > the B-E current vs C-E current properties change over temperature and amo= unt > of amplification. Also, I don't think you /really/ need that capacitor > there. > Since this is a simple low current application, you can get awesome battery charger ICs from Linear and National that do exactly what you're looking fo= r for less than the price of a coffee. Check these out this linear NiMH charger (I love this one, it rocks): LTC4060 http://www.linear.com/product/LTC4060 ~$4.50 in singles, exactly what you need. Just order a sample if one is all you need. --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .