R
Roger Hamlett
For efficiency, you would want to use a switching regulator for bothjasonbot said:The maxim chip seems great but maybe a little complex, I got my ideas
from here:
http://www.instructables.com/id/EGBQJPLCB2EP287KTZ/#CEVEIRM4776EP288H78
And would now like to expand on the idea, I dont want to buy the kit
because I want to marvel at my own design, I have a basic idea but now
need to put th eplan into action. How woul 4 AA's 6V with a regulator
compare with the 3V step up, the 6V would be much easier.
routes. The 'down' switcher, removed the need for the inductor, but
remember that you would only be able to discharge the batteries to just
over 1.25v, before you lose the ability to deliver 5v, which will give
less utilisation of the available power in the cells. Realistically, the
boost regulator, done with an IC, designed to do this, should quite easily
get over 90% efficiency, and use ost of the available power in the cells
as well. However remember that board design round a switching regulator,
needs to be carefully done...
The battery in the last Ipod Ilooked at, was only a 150mAHr cell, and this
was quoted to give 3 hours typical life (giving a consumption of perhaps
only perhaps 50mA to 60mA - given the extra losses at the '3 hour' rate,
versus the power normally quoted at the '10 hour' rate). The circuitry
drew about 400mA, _when charging_ the battery.
Best Wishes