The DS2720 single-cell rechargeable Li+ protection IC provides electronic safety functions required for rechargeable Li+ applications including protecting the battery during charge, protection of the circuit from damage during periods of excess current flow and maximization of battery life by limiting the level of cell depletion. Protection is facilitated by electronically disconnecting the charge and discharge conduction path with switching devices such as low-cost N-channel power MOSFETs. Since the DS2720 provides high-side drive to external N-channel protection MOSFETs from a 9V charge pump, superior on-resistance performance results compared to common low-side protector circuits using the same FETs. The FET on-resistance actually decreases as the battery discharges. Adding to the uniqueness of the DS2720 is the ability of the system to control the FETs from either the data interface or a dedicated input thereby eliminating the power-switch control redundancy of rechargeable Li+ battery systems. Through its 1-Wire interface, the DS2720 gives the host system read/write access to status and control registers, instrumentation registers, and general-purpose data storage. Each device has a factoryprogrammed 64-bit net address that allows it to be individually addressed by the host system. 1-Wire is a registered trademark of Dallas Semiconductor.