Input
All PSP chargers work on a range of voltages from 100V to 240V, with alternating current (AC). If you are traveling to a European country, in which the standard voltage is 240V, you don't need to connect the PSP charger to a transformer; it can convert 240V to what it needs.
Output
The charger for the PSP 1001 and PSP 2001 models never changes, but the PSP 3001 uses a different charger. The first two require an output of 2000 miliAmps, or mA (2 amps), while the 3001's charger pumps out 1500 mA (1.5 amps). This goes into the PSP at 5V direct current (DC).
Size and Shape
The charging devices are rectangular, with a PSP-compatible power lead connected directly to one end of the box. The other end has a slot compatible with a wall lead, included with your PSP device. The chargers for the PSP 1001 and 2001 are 1.8 inches by .8 inches by 3 inches, while the 3001 charger is slightly shorter: 1.8 inches by .8 inches by 2.4 inches.
Weight
The transforming device weighs slightly less on the 3001 charger, weighing in at 57 grams. The older devices have a heavier charger, at 100 grams.