AVR-Chat

--- In AVR-Chat@yahoogroups.com, "C Sizer" <aussiecol39@y...> wrote:

> ... of course NiMH will only give
> me around 2.4V in this configuation.

Col, I think this thread has got confused by people not reading your 
original post and disagreeing with perfectly workable solutions.

Four NiMH cells in series will give you 5V if they are fully charged. 
This will sag a bit when the printer draws off 3.5A and also as the 
cells discharge. I would hope that the printer continues to work down 
to some lower voltage, but you will have to find that out.

Your series/parallel idea to increase capacity is really not such a 
good idea if you have to boost convert to a higher voltage. The extra 
capacity is lost to converter inefficiency.

Think again about my proposal.

Graham.