Texas Instruments bq25731 Buck-Boost Battery Charge Controller
Texas Instruments bq25731 Buck-Boost Battery Charge Controller is a synchronous buck-boost battery charge controller. It can be used to charge a 1- to 5-cell battery from a wide range of input sources, including a USB adapter, high voltage USB-C Power Delivery (PD) sources, and traditional adapters. It offers a low component count, high-efficiency solution for space-constrained, 1- to 5-cell battery charging applications. During power-up, the charger sets the converter to a buck, boost, or buck-boost configuration based on the input source and battery conditions. The charger seamlessly transits between the buck, boost, and buck-boost operation modes without host control.
In the absence of an input source, the Texas Instruments bq25731 supports the USB On-the-Go (OTG) function from a 1- to 5-cell battery to generate an adjustable 3V to 24V output on VBUS with 8mV resolution. The OTG output voltage transition slew rate can be configured to comply with the USB-PD 3.0 PPS specification. The latest version of the USB-C PD specification includes Fast Role Swap (FRS) to ensure power role swapping occurs in a timely fashion so that the device(s) connected to the dock can avoid experiencing momentary power loss or glitching. This device integrates FRS in compliance with the PD specification.
Features
- No battery MOSFET for saving cost and high efficiency
- 400kHz/800kHz programmable switching frequency for high efficiency/high power density
- Buck-boost charger for USB-C Power Delivery (PD) interface platform
- 3.5V to 26V input range to charge 1- to 5-cell battery
- Charge current up to 16.2A/8.1A with 128mA/64mA resolution based on 5mΩ/10mΩ sensing resistor
- Input current limit up to 10A/6.35A with 100mA/50mA resolution based on 5mΩ/10mΩ sensing resistor
- Support USB 2.0, USB 3.0, USB 3.1 and USB power delivery input current setting
- Input Current Optimizer (ICO) to extract max input power without overloading the adapter
- Seamless transition between buck, buck-boost, and boost operations
- Input current and voltage regulation (IINDPM and VINDPM) against source overload
- TI patented switching frequency dithering pattern for meeting IEC-CISPR 32 EMI specification
- TI patented Pass-Through Mode (PTM) for system power efficiency improvement and battery fast charging, achieving 99% efficiency
- Input and battery current monitor through dedicated pins
- Integrated 8-bit ADC to monitor voltage, current, and power
- Support independent comparator logic with dedicated pins
- Power up USB port from the battery (USB OTG)
- 3V to 24V OTG with 8mV resolution
- Output current limit up to 12.7A/6.35A with 100mA/50mA resolution based on 5mΩ/10mΩ sensing resistor
- I2C host control interface for flexible system configuration
- High accuracy for the regulation and monitor
- ±0.5% Charge voltage regulation
- ±3% Charge current regulation
- ±2.5% Input current regulation
- ±2% Input/charge current monitor
- Safety
- Thermal shutdown
- Input, system, battery overvoltage protection
- Input, MOSFET, inductor overcurrent protection
- Package: 32-Pin 4.0mm × 4.0mm WQFN
Applications
- Cordless power tool
- Battery pack
- Cordless power tool
- Appliances
- Battery charger
- Power bank
Application Diagram
Related Development Tool
Texas Instruments bq2573xEVM Controller Evaluation Module (EVM)
For the evaluation of the bq2573x, a I2C 1-5 cell NVDC buck-boost battery charge controller.