Tamas Rudnai wrote:
> As far as I understood solarwind does not want to put a dc-dc in his
> application, and that's where all the problems occur. In other words
> he cannot guarantee stable USB voltage level,

But the point is he can well enough.  Four NiMH batteries will produce righ=
t
around 5V when full.  At 1.05V per cell the voltage drops to 4.2V, which is
just a fraction below the minimum USB voltage.  Since Apple is drawing
higher than normal currents, they have to be prepared for a larger cable
drop, so most likely the phone will still charge at 4.2V and a bit lower.

At 1.05V there is still some capacity left in a NiMH cell, but a good
fraction has been used.  Also the phone will likely charge with a bit lower=
..
A simple test with a variable power supply would confirm this, but the OP i=
s
stubbornly refusing to do that.


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