●The bq24721 is a high efficiency synchronous battery pack charger with high level of integration for portable applications. This device implements a high performance analog front-end that interfaces to the system power management micro-controller through a simplified SBS-like SMBus interface.
●The dynamic power management (DPM) function modifies the charge current depending on system load conditions, avoiding ac adapter overload.
●High accuracy current sense amplifiers enable accurate measurement of either the charge current or the ac adapter current, allowing termination of nonsmart packs and monitoring of overall system power.
●The adapter isolation diode can be bypassed or entirely replaced with an external MOSFET using a control signal provided by the bq24721, thus reducing overall power dissipation.
●Integrated features such as charger soft start, charge overcurrent protection, and IC temperature monitoring provide a second level of protection, in addition to pack and system protection functions.
● High Efficiency NMOS-NMOS Synchronous Buck Converter With User-Selectable 300 kHz or 500 kHz frequency
● bq24721C Offers Softer Turn-On, Stronger Turn-Off
● SBS-Like(1) SMBus Interface for Control and Status Communications With Host
● Programmable Battery Voltage, Charge Current, and AC Adapter Current via SBS-Like SMBus Interface
● 0.4% Charge Voltage Regulation Accuracy
● 3% Charge Current Regulation Accuracy
● 3% Adapter Current Regulation Accuracy Dynamic Power Management (DPM)
● 2% Accuracy Integrated Charge and AC Adapter 20× Current Amplifier Output
● 3-Cell and 4-Cell Li-Ion Voltage Regulation 9 V, 12 V-14.4 V, 16 V-19.2 V
● Battery Pack Voltage Operating Range 0 V-19.2 V
● AC Adapter Operating Range 8 V-28 V
● 99.5% Max Duty Cycle
● Internal Soft Start
● Integrated 5% 5-V LDO When AC Adapter Applied
● 6-V Drive Supply Voltage for Increased Efficiency
● Reverse Battery to Adapter Discharge Protection
● Battery/Adapter to System Power Selector Function
● Charge and Adapter Overcurrent Protection
● Battery Thermistor Sense, TS, Comparators
● Available in 32-Pin 5x5-mm QFN Package
● APPLICATIONS
● Portable Notebook Computers
● Portable DVD Players
● Webpads, 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.
●PowerPAD is a trademark of Texas Instruments.
