Texas Instruments bq24157S Switch-Mode One-Cell Li-Ion Charger IC

Texas Instruments bq24157S Switch-Mode One-Cell Li-Ion Charger IC 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 a synchronous PWM controller, power MOSFETs, input current sensing, high-accuracy current and voltage regulation, and charge termination, into a small DSBGA package. The Texas Instruments bq24157S 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. The charge is terminated based on battery voltage and user-selectable minimum current level. A safety timer with reset control provides a safety backup for the I²C interface.

Features

Integrated Power FETs for up to 1.55A Charge Rate
Spread Spectrum Frequency Control for Improved EMI Performance
High-Accuracy Voltage and Current Regulation
- Input Current Regulation Accuracy: ±5% (100mA and 500mA)
- Charge Voltage Regulation Accuracy: ±0.5% (25°C), ±1% (0°C to 125°)
- Charge Current Regulation Accuracy: °5%
Factory Test-Mode for GSM Calibration Without a Battery
Input Voltage Based Dynamic Power Management (V_IN DPM)
Bad Adaptor Detection and Rejection
Safety Limit Register for Maximum Charge Voltage and Current Limiting
Programmable Charge Parameters through I²C Compatible Interface (up to 3.4Mbps)
- Input Current Limit
- V_IN DPM Threshold
- Fast-Charge/Termination Current
- Charge Regulation Voltage (3.5 to 4.44V)
- Low Charge Current Mode Enable/Disable
- Safety Timer with Reset Control
- Termination Enable/Disable

High-Efficiency Mini-USB/AC Battery Charger for Single-Cell Li-Ion and Li-Polymer Battery Packs
20V Absolute Maximum Input Voltage Rating
6.5V Maximum Operating Input Voltage
Synchronous Fixed-Frequency PWM Controller Operating at 3MHz 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 Overvoltage Protection
Status Output for Charging and Faults
USB Friendly Boot-Up Sequence
Automatic Charging
Power Up System Without Battery
Boost Mode Operation for USB OTG
- Input Voltage Range (from Battery): 3.2 to 4.5V
- Output for V_BUS: 5.05 , 350mA
2.25 × 2.65mm, 20-Pin DSBGA Package
Pin-to-Pin Compatible With bq24157 and bq24158