Nonya said:
Better make sure it is low amps. Or you will fry it. USB outout is very
low amps.
If you mean, make sure the power supply has a low amperage rating, that
makes no sense. The amperage rating of the power supply only needs to be
high enough; as long as it's above the amount you need, you're fine - unless
the voltage goes too high. If you need 5V, and you're trying to get, say
100mA (I have no idea if that's realistic but it's just an example), you'll
get 100mA unless the power supply is not able to push that current. You
won't get more. So even if the supply is rated for 5A, you're fine unless it
tries to put out a higher voltage. You'll still only draw those 100mA. See
what I mean:
Ohm's Law:
V=IR where R is the resistance of the load (the MP3 player), which won't
change beyond a certain specified point. So consider R a constant.
So, I, the current drawn, is directly proportional to V. If you want to get
a higher current I, you'll have to bring up V. A power supply won't push up
the voltage in order to give more current.
(Sorry if I'm verbose, it's my first post; I just got excited. I'll die
laughing if I just misunderstood your post!)