The BQ2409x series of devices are highly integrated Li-ion and Li-Pol linear chargers devices targeted at space-limited portable applications. The devices operate from either a USB port or AC adapter. The high input voltage range with input overvoltage protection supports low-cost unregulated adapters.

The BQ2409x has a single power output that charges the battery. A system load can be placed in parallel with the battery as long as the average system load does not keep the battery from charging fully during the 10-hour safety timer.

The battery is charged in three phases: conditioning, constant current and constant voltage. In all charge phases, an internal control loop monitors the IC junction temperature and reduces the charge current if an internal temperature threshold is exceeded.

The charger power stage and charge current sense functions are fully integrated. The charger function has high accuracy current and voltage regulation loops, charge status display, and charge termination. The pre-charge current and termination current threshold are programmed via an external resistor. The fast charge current value is also programmable via an external resistor.

• Charging
  • 1% charge voltage accuracy
  • 10% charge current accuracy
  • Pin selectable USB 100-mA and 500-mA maximum input current limit
  • Programmable termination and precharge threshold
• Protection
  • 6.6-V overvoltage protection
  • Input voltage dynamic power management
  • 125°C thermal regulation; 150°C thermal shutdown protection
  • OUT short-circuit protection and ISET short detection
  • Operation over JEITA range via battery NTC – ? fast-charge-current at cold, 4.06 V at hot, BQ092/3
  • Fixed 10-hour safety timer
• System
  • Automatic Termination and Timer Disable Mode (TTDM) for absent battery pack with thermistor
  • Status indication – charging/done
  • Available in a small 10-pin MSOP package

• Number of series cells
• 1
• Charge current (Max) (A)
• 1
• Operating Vin (Max) (V)
• 6.45
• Cell chemistry
• Li-Ion/Li-Polymer
• Battery charge voltage (Min) (V)
• 4.2
• Battery charge voltage (Max) (V)
• 4.2
• Absolute Vin (safety rating) (Max) ((V))
• 12
• Control interface
• Standalone (RC-Settable)
• Features
• BAT temp thermistor monitoring (hot/cold profile), IC thermal regulation, Input OVP, VINDPM (Input voltage threshold to maximize adaptor power)
• Operating Vin (Min) (V)
• 4.45
• Rating
• Catalog

BQ24091的完整型号有：BQ24091DGQR、BQ24091DGQT，以下是这些产品的关键参数及官网采购报价：

BQ24091DGQR，工作温度：-40 to 150，封装：HVSSOP (DGQ)-10，包装数量MPQ：2500个，MSL 等级/回流焊峰值温度：Level-1-260C-UNLIM，引脚镀层/焊球材料：NIPDAUAG，TI官网BQ24091DGQR的批量USD价格：.541（1000+）

BQ24091DGQT，工作温度：-40 to 150，封装：HVSSOP (DGQ)-10，包装数量MPQ：250个，MSL 等级/回流焊峰值温度：Level-1-260C-UNLIM，引脚镀层/焊球材料：NIPDAUAG，TI官网BQ24091DGQT的批量USD价格：.649（1000+）

BQ24091EVM — BQ24091 评估模块

BQ24091EVM 用户指南介绍了 bq24091 评估模块 (EVM)、如何执行独立评估或与主机或系统交互。该充电器设计为在 ISET 引脚上设定电阻以及在出厂时设定好 ~540mA 时向电池输出提供高达 1000mA 的连续电流。USB 电流限制模式由 ISET2 引脚选择，并将电流限制为最大 500mA（逻辑高电平）或 100mA（浮点或高阻抗）。ISET2 引脚上的低电阻使用 ISET 电阻对充电电流进行编程。

Linear Charger NTC Calculator

当使用 ISET 引脚上的电阻器编程时，此参考设计可为电池输出提供高达 1000mA 的连续电流，并且在出厂时编程为 ~540mA。USB 电流限制模式由 ISET2 引脚选择，并将电流限制为最大 500mA（逻辑高电平）或 100mA（浮点或高阻抗）。ISET2 引脚上的低电阻使用 ISET 电阻对充电电流进行编程。