To conserve the battery's charge, the Reader includes automatic power saving modes. The Reader will enter sleep mode after 10 minutes of inactivity. After 3 days* in sleep mode, the Reader will shut down/power off automatically.
However, when playing audio or viewing a slideshow, this feature does not work. The automatic power saving modes cannot be turned off.
*If the battery's charge is low, the Reader may automatically turn off within 3 days.