 A sleep mode is also available that uses minimal battery power to keep the system's RAM active, allowing for "instant on" functionality.A system in sleep mode (with a fully charged battery) has been shown to lose an average of only 1% battery life per 24-hour period.The PSP-1000 series is equipped with a two-pin docking connector immediately below the AC adapter jack for easy drop in charging using a docking station that was to be sold separately.