The PSP or Playstation Portable handheld gaming device uses an internal battery to provide power to the device. You can use a USB cable connected to your computer to recharge the battery for more gaming as long as you have previously enabled the USB charging feature in the system's settings. Otherwise you will have to use an external AC adapter with the USB cable if the battery is fully dead and you cannot make changes to the settings.
Connect the power cable to your computer or other USB enabled device that will provide a charge to the PSP.
Plug one end of the USB cable into an open USB port on your computer.
Insert the other end into the USB jack on the bottom of the PSP. The power indicator will glow orange when the charging has begun.
USB with AC Adapter
Plug one end of the USB cable into the port on the bottom of the PSP.
Insert the other end into the USB port on the AC adapter.
Plug one end of the AC power chord into the port on the other side of the adapter and plug the other end into a nearby power outlet.