... DVD, NDSL, PSP, MP3/MP4, iPod, iPhone, iPadHow to know the remain power.Press the button, LED lights will ... seconds, LED lights turn on, the charger begins to charge. 4. After charging, keep pressing the button ... for 3 seconds to turn off the charger, 5. Keep the units ... power3)Press the button for 3 seconds to active or shutdown USB output4)5 LEDs turn on ...