DESCRIPTION
●The bq24157 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 WCSP package.
●FEATURES
●• Power Up System without Battery
●• Charge Faster than Linear Chargers
●• High-Accuracy Voltage and Current Regulation
●– Input Current Regulation Accuracy: ±5% (100 mA and 500 mA)
●– Charge Voltage Regulation Accuracy: ±0.5% (25°C), ±1% (0°C to 125°C)
●– Charge Current Regulation Accuracy: ±5%
●• Input Voltage Based Dynamic Power Management (VIN DPM)
●• Bad Adaptor Detection and Rejection
●• Safety Limit Register for Maximum Charge Voltage and Current Limiting
●• High-Efficiency Mini-USB/AC Battery Charger for Single-Cell Li-Ion and Li-Polymer Battery Packs
●• 20-V Absolute Maximum Input Voltage Rating
●• 6.5-V Maximum Operating Input Voltage
●• Built-In Input Current Sensing and Limiting
●• Integrated Power FETs for Up To 1.25-A Charge Rate
●• Programmable Charge Parameters through I2C™ Compatible Interface (up to 3.4 Mbps):
●– Input Current Limit
●– VIN DPM Threshold
●– Fast-Charge/Termination Current
●– Charge Regulation Voltage (3.5 V to 4.44 V)
●– Low Charge Current Mode Enable/Disable
●– Termination Enable/Disable
●• 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 Overvoltage Protection
●• Status Output for Charging and Faults
●• USB Friendly Boot-Up Sequence
●• Automatic Charging
●• Boost Mode Operation for USB OTG
●– Input Voltage Range (from Battery): 3.2 V to 4.5 V
●• 2.1 mm x 2 mm 20-Pin WCSP Package
●APPLICATIONS
●• Mobile and Smart Phones
●• MP3 Players
●• Handheld Devices
