bq24721 bq24721C
www. ti. com. SLUS683F – NOVEMBER 2005 – REVISED APRIL 2009
ADVANCED MULTI-CHEMISTRY AND MULTI-CELL SYNCHRONOUS SWITCH-MODE CHARGER AND SYSTEM POWER SELECTOR
FEATURES
1
•2 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
(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 Table 1 for a comparison between SBS-like vs SBS Specification.
FBO 9 AGND 10 VREF5 11
VCC 12 SDA 13 SCL 14
TS 15 ISYNSET 16
APPLICATIONS
• Portable Notebook Computers • Portable DVD Players • Webpads, PC Tablets
DESCRIPTION
The bq24721 is a high efficiency synchronous battery pack cha...
bq24721C PDF File
