V G wrote:
> Would there be a way to put a regulator of some sort on there that
> would
> drop the voltage to 5.5 volts if the input voltage is higher, but
> still pass current through even when voltage is below 5.5 volts (for
> example).

That would need to be a "low dropout" regulator, and is always going to dro=
p
some voltage.  These are also hard to come by at 1A.  If you're clever, you
could possibly design your own with a carefully chosen FET as the pass
element.  One advantage you have is that since the phone is floating, you
can put the pass element on the low side instead of the high side.  N FETs
are a little easier to find with better specs than P FETs, and the circuit
will probably be conceptually a little easier.

However, I would be very very surprised if your phone will have a problem a=
t
a few 100 mV above the valid USB power range.


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