High Efficiency NMOS-NMOS Synchronous Buck Converter With User-Selectable 300 kHz or 500 kHz frequency bq24721C Offers Softer Turn-On, Stronger Turn-OffSBS-Like(1) SMBus Interface for Control and Status Communications With HostProgrammable Battery Voltage, Charge Current, and AC Adapter Current via SBS-Like SMBus Interface0.4% Charge Voltage Regulation Accuracy3% Charge Current Regulation Accuracy3% Adapter Current Regulation Accuracy Dynamic Power Management (DPM)2% Accuracy Integrated Charge and AC Adapter 20× Current Amplifier Output3-Cell and 4-Cell Li-Ion Voltage Regulation 9 V, 12 V-14.4 V, 16 V-19.2 VBattery Pack Voltage Operating Range 0 V-19.2 VAC Adapter Operating Range 8 V-28 V99.5% Max Duty CycleInternal Soft StartIntegrated 5% 5-V LDO When AC Adapter Applied6-V Drive Supply Voltage for Increased EfficiencyReverse Battery to Adapter Discharge ProtectionBattery/Adapter to System Power Selector FunctionCharge and Adapter Overcurrent Protection Battery Thermistor Sense, TS, ComparatorsAvailable in 32-Pin 5x5-mm QFN PackageAPPLICATIONSPortable Notebook ComputersPortable DVD PlayersWebpads, PC Tablets (1) SBS-Like interface is not 100% SBS compliant. SBS-Like interface is SMBus1.1 complaint but does not support Packet Error Correction (PEC). The control and status registers were changed to simplify and enhance notebook charger control. An 8-bit address (0x12) is used. See for a comparison between SBS-like vs SBS Specification.PowerPAD is a trademark of Texas Instruments.