The bq24140 is a compact, flexible, high-efficiency, USB-friendly switch-mode charge management device for single-cell Li-ion and Li-polymer batteries used in a wide range of portable applications. The charge parameters can be programmed through an I2C interface. The IC integrates two synchronous PWM chargers, power MOSFETs, input current sensing, high-accuracy current and voltage regulation, and charge termination, into a small WCSP package.
The IC charges the battery in three phases: conditioning, constant current and constant voltage. The input current is automatically limited to the value set by the host. Charge is terminated based on user-selectable minimum current level. A safety timer with reset control provides a safety backup for I2C interface. During normal operation, the IC automatically restarts the charge cycle if the battery voltage falls below an internal threshold and automatically enters sleep mode or high impedance mode when the input supply is removed. The charge status can be reported to the host using the I2C interface. During the charging process, the IC monitors its junction temperature (TJ) and reduces the charge current once TJ increases to125°C typical. To support USB OTG device, the IC can provide VBUS (5.05V typical) by boosting the battery voltage. The IC is available in 30-pin WCSP package.
Feature
- High-Efficiency Mini-USB/AC Battery Charger for
Single-Cell Li-Ion and Li-Polymer Battery Packs - Charge Battery and Provide USB-OTG Support at the Same Time
- High-Accuracy Voltage and Current Regulation
- Input Current Regulation Accuracy: ±5% (100mA, 500mA)
- Charge Voltage Regulation Accuracy: ±0.5% (25°C), ±1% (0-125°C)
- Charge Current Regulation Accuracy: ±5%
- Boost Mode Operation for USB OTG:
- Input Voltage Range (from Battery): 2.3V to 4.5V
- Output for VBUS: 5.05V/500 mA
- Input Voltage Based Dynamic Power Management Provides
Protection Against Current Limited Adapters - Bad Adaptor Detection and Rejection
- Safety Limit Register for Added Security by Limiting
Maximum Charge Voltage and Maximum Charge Current - 20-V Absolute Maximum Input Voltage Rating
- 9.0-V Maximum Operating Input Voltage
- Charge Faster than Linear Chargers
- Built-in Input Current Sensing and Limiting
- Integrated Power FETs for up to 1.5-A Charge Rate
- Programmable Charge Parameters Through I2C Interface
(up to 3.4 Mbps):- Input Current
- Fast-Charge/Termination Current
- Charge Voltage (3.5-4.44V)
- Safety Timer with Reset Control
- Safety Timer with Reset Control
- Termination Enable
- Synchronous Fixed-Frequency PWM Controller Operating at 3 MHz
With 0% to 99.5% Duty Cycle - Automatic High Impedance Mode for Low Power Consumption
- Robust Protection
- Reverse Leakage Protection Prevents Battery Drainage
- Thermal Regulation and Protection
- Input/Output Over Voltage Protection
- Status Output for Charging and Faults
- USB Friendly Boot-Up Sequence
- 2.35 × 2.65 mm 30-pin WCSP Package
