The BQ25731 is a synchronous buck-boost battery charge controller to charge a 1- to 5-cell battery from a wide range of input sources including 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.

• No battery MOSFET for saving cost and high efficiency
• 400-kHz/800-kHz programmable switching frequency for high efficiency/high power density
• Buck-boost charger for USB-C Power Delivery (PD) interface platform
  • 3.5-V to 26-V input range to charge 1- to 5-cell battery
  • Charge current up to 16.2 A/8.1 A with 128-mA/64-mA resolution based on 5-mΩ/10-mΩ sensing resistor
  • Input current limit up to 10 A/6.35 A with 100-mA/50-mA resolution based on 5-mΩ/10-mΩ sensing resistor
  • Support USB 2.0, USB 3.0, USB 3.1 and USB Power Delivery (PD)
  • 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 EMI noise reduction
• 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 battery (USB OTG)
  • 3-V to 24-V OTG with 8-mV resolution
  • Output current limit up to 12.7 A/6.35 A with 100-mA/50-mA resolution based on 5-mΩ/10-mΩ 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 4.0 mm × 4.0 mm WQFN

• Number of series cells
• 1, 2, 3, 4, 5
• Charge current (Max) (A)
• 16.2
• Operating Vin (Max) (V)
• 26
• Cell chemistry
• Lead Acid, Li-Ion/Li-Polymer, Lithium Phosphate/LiFePO4, NiCd, NiMH, SuperCap
• Battery charge voltage (Min) (V)
• 1.024
• Battery charge voltage (Max) (V)
• 23
• Absolute Vin (safety rating) (Max) ((V))
• 32
• Control interface
• I2C
• Features
• IC thermal regulation, ICO (Input Current Optimization), IINDPM (Input current limit), Input OVP, Integrated ADC, USB C/PD compatible, USB OTG integrated, VINDPM (Input voltage threshold to maximize adaptor power)
• Operating Vin (Min) (V)
• 3.5
• Rating
• Catalog

BQ25731的完整型号有：BQ25731RSNR，以下是这些产品的关键参数及官网采购报价：

BQ25731RSNR，工作温度：-40 to 85，封装：QFN (RSN)-32，包装数量MPQ：3000个，MSL 等级/回流焊峰值温度：Level-2-260C-1 YEAR，引脚镀层/焊球材料：NIPDAU，TI官网BQ25731RSNR的批量USD价格：1.35（1000+）

BQ25731EVM — I2C NVDC 1 至 5 节电池 16A 降压/升压充电器控制器评估模块

BQ25731EVM 评估模块 (EVM) 是一款具有 N 沟道 MOSFET 选择器和电流监控功能的 I2C 控制型 NVDC（窄电压直流）降压/升压充电控制器。降压转换器的输入电压范围为 3.5V 至 26V，并具有 1-5 节电池的可编程输出以及 128mA 至 15A 的充电输出电流范围。此 EVM 不含 EV2400 接口器件；如需评估 BQ25731 EVM，则须单独订购此器件。

BQSTUDIO-TEST — Battery Management Studio (bqStudio) 软件 – 未测试版本下载

TI-CHARGER-GUI 提供基于网络的或独立的图形用户界面，可辅助评估、设计、配置或测试电池充电器产品。该软件可实现对寄存器的全面访问，并提供一个简单接口用于发送时序命令。

PMP41013 — Integrated USB Type-C PD bidirectional charging reference design for one- to five-cell batteries

This reference design is an integrated USB Type-C power delivery (PD) and charging reference design for one- to five-cell batteries for applications such as power tool charger with USB Type-C port, vacuum cleaner, portable power station and more.

TIDA-010240 — 可扩展的多智能电池包充电器参考设计

超过 100 瓦时 (Wh) 的锂电池通常不允许放在随身行李中，除非航空公司自行规定并需要事先批准。该参考设计是一种智能高效充电器设计，适用于高达 100Wh 的双智能电池包（实际为采用并联配置的 1 节至 5 节锂离子电池）。

PMP22805 — 带有 USB On-The-Go (OTG) 的 24VIN、240W、效率为 98% 的紧凑型 5 节电池充电器参考设计

此电池充电器参考设计用于 5 至 24VIN、240W 电动工具，配备 BQ25731 一至五节电池 NVDC 降压/升压电池充电控制器。这是大功率、高效率和高密度设计。PMP22805 提供 240W 功率，效率为 98%，适合紧凑型 1.08 英寸 x 1.68 英寸 (27.4mm x 42.7mm) 外形尺寸。USB On-The-Go (OTG) 功能使之成为移动电源。它非常适合设计重点是大功率、高效率和高密度的电动工具。此参考设计支持 1 至 5 节电池，可接受宽输入范围，例如 USB Type-C PD 接口。