TI BQ25892RTWR

The BQ25890 and BQ25892 are highly integrated 5A switch-mode battery charging and system power path management devices for single-cell Li-Ion and Li-Polymer batteries. These devices support high input voltage fast charging. The low-impedance power path optimizes switch-mode operation efficiency, reduces battery charge time, and extends battery life during the discharge phase.

The I²C serial interface with charge and system settings makes these devices a truly flexible solution. The devices support multiple input sources, including standard USB host ports, USB charging ports, and USB-compatible adjustable high-voltage adapters. To support fast charging via adjustable high-voltage adapters, the BQ25890 provides MaxCharge™ handshake support (using D+/D- pins and the DSEL pin) for USB switch control. In addition, the BQ25890 and BQ25892 provide corresponding interfaces to support adjustable high-voltage adapters using input current pulse protocols. To set the default input current limit, the device uses the built-in USB interface (BQ25890) or obtains results from system detection circuits such as USBPHY devices (BQ25892). The devices comply with USB 2.0 and USB 3.0 power specifications, featuring input current and voltage regulation. Furthermore, the Input Current Optimizer (ICO) can detect the maximum power point when the input source is not overloaded. The device also features current limiting capability of up to 2.4A, capable of providing 5V (adjustable from 4.5V to 5.5V) to VBUS, compliant with USB On-the-Go (OTG) operating power rating specifications.

Power path management regulates the system voltage to slightly above the battery voltage, but prevents it from dropping below the 3.5V minimum system voltage (programmable). With this feature, the system remains operational even when the battery is completely discharged or removed. When the input current or voltage limit is reached, power path management technology automatically reduces the charge current to 0. As the system load continues to increase, the power path discharges the battery until system power demands are met. This supplement mode operation prevents input source overload.

The device initiates and completes a charge cycle without software control. It automatically detects the battery voltage and charges the battery through three phases: pre-charge, constant current, and constant voltage.

• High-efficiency 5A, 1.5MHz switch-mode buck charging
• 93% charging efficiency at 2A charging current; 91% at 3A charging current
• Optimized for high-voltage input (9V to 12V)
• Low-power PFM mode for light-load operation
• USB OTG with adjustable output voltage range of 4.5V to 5.5V
• Boost converter with up to 2.4A output and selectable 500kHz or 1.5MHz switching frequency
• 93% boost efficiency at 5V (1A) output
• Accurate discontinuous-mode overcurrent protection
• Single input supporting USB input and adjustable high-voltage adapter
• Supports 3.9V to 14V input voltage range
• Input current limit (100mA to 3.25A, 50mA resolution) supporting USB2.0, USB3.0, and high-voltage adapters
• Maximum power tracking via input voltage limit up to 14V for various adapters
• Auto-detection of USB SDP, CDP, DCP, and non-standard adapters (BQ25890)
• Input Current Optimizer (ICO) for maximizing input power without overloading the adapter
• IR compensation (IRCOMP) between charger output and battery terminal
• Ultra-high battery discharge efficiency via 11mΩ battery discharge MOSFET with discharge current up to 9A
• Integrated ADC for system monitoring (voltage, temperature, and charging current)
• Narrow VDC (NVDC) power path management
• Instant-on operation without battery or with deeply discharged battery
• Ideal diode operation in battery charging mode
• BATFET control supporting shipping mode, wake-up, and full system reset
• Flexible autonomous and I2C modes for optimized system performance
• High integration including all MOSFETs, current sensing, and loop compensation
• 12μA low battery leakage current with shipping mode support
• High accuracy
  • ±0.5% charge voltage regulation
  • ±5% charge current regulation
  • ±7.5% input current regulation
• Safety
  • Battery temperature monitoring for charging and boost modes
  • Thermal regulation and thermal shutdown

• Smartphones
• Tablets
• Portable network devices