The bq24725 is a high-efficiency,synchronous battery charger, offering low component count for space-constraint, multi-chemistry battery charging applications.
The bq24725 uses two charge pumps to separately drive n-channel MOSFETs (ACFET, RBFET and BATFET) for automatic system power source selection.
SMBus controlled input current, charge current, and charge voltage DACs allow for high regulation accuracies that can be programmed by the system power management micro-controller.
The bq24725 uses internal input current register or external ILIM pin to throttle down PWM modulation to reduce the charge current.
The bq24725 chargestwo, three or four series Li+ cells, and is available in a 20-pin, 3.5 × 3.5 mm2 QFN package.
Feature
- SMBus Host-Controlled NMOS-NMOS Synchronous Buck Converter with
Programmable 615kHz, 750kHz, and 885kHz Switching Frequencies - Automatic N-channel MOSFET Selection of System Power Source from
Adapter or Battery Driven by Internal Charge Pumps - Enhanced Safety Features for Over Voltage Protection, Over Current
Protection, Battery, Inductor and MOSFET Short Circuit Protection - Programmable Input Current, Charge Voltage, Charge Current Limits
- ±0.5% Charge Voltage Accuracy up to 19.2V
- ±3% Charge Current Accuracy up to 8.128A
- ±3% Input Current Accuracy up to 8.064A
- ±2% 20x Adapter Current or Charge Current Amplifier
Output Accuracy
- Programmable Battery Depletion Threshold, and Battery LERAN Function
- Programmable Adapter Detection and Indicator
- Integrated Soft Start
- Integrated Loop Compensation
- Real Time System Control on ILIM pin to Limit Charge Current
- AC Adapter Operating Range 9V-24V
- 5μA Off-State Battery Discharge Current
- 20-pin 3.5 × 3.5 mm2 QFN Package
- APPLICATIONS
- Portable Notebook Computers, UMPC, Ultra-Thin Notebook, and Netbook
- Personal Digital Assistant
- Handheld Terminal
- Industrial and Medical Equipment
- Portable Equipment
