In article ,
Rich Greenberg wrote:
In article ,
Frank wrote:
Does it make any difference on output amperage if output voltage is the
same in wall plug/USB charger adapters? Referring to 1 amp vs 1.8 amps.
Former is for iPhone & latter for Kindle Fire HD. Was hoping to use one
of these adapters rather than having to buy another one for Samsung
Intensity II phone. Both have 5 volts output.

Volts o/p is a specification. Amps o/p is a maximum capability.
So if you have a wall wart rated 5 volts & 1.8 amps, it can be use for
anything that wants 5 volts and up to 1.8 amps. Your 1 amp Iphone will
run fine, just a bit cooler.

No cooler; the iPhone will draw it's usual amount of current (if the
adapter can supply it, which should be no problem in this case) and will
dissipate the same amount of heat. If it's noticably warmer or cooler,
then something is wrong.

Exception: If the Kindle charger is poorly designed, it MAY need the
full 1.8 amp o/p to pull the voltage down to 5. Measure the voltage it
puts out when connected to the Iphone.

No, voltage is what's regulated and should be stable over the full range
of current draw. Unregulated wall warts haven't been made for years; the
newer switching power supplies are much better at regulating and much
lighter weight as well.


Gary