Patent ID: 7560829

Claim:
An apparatus comprising: a first battery port to couple to a first type of battery pack having a first battery voltage range; a second battery port to couple to a second type of battery pack having a second battery voltage range that is different from the first battery voltage range; a first power rail to couple to a first set of loads that collectively operate with a higher efficiency in the first battery voltage range than the second battery voltage range; a second power rail to couple to a second set of loads that collectively operate with a higher efficiency in the second battery voltage range than the first battery voltage range; and a switch circuit having a plurality of switch settings, said plurality of switch settings comprising an increased efficiency setting to couple the first battery port to the first power rail and the second battery port to the second power rail, a second setting to couple the first battery port to both the first power rail and the second power rail, and a third setting to couple the second battery port to both the first power rail and the second power rail.