Switch Mode Charger Li-Ion/Li-Pol Packs 1550mA 4.5V 25-Pin WLCSP T/R

The FAN5404X family includes I2C controlled 1.55 A USBcompliant switch-mode chargers with power path operation and USB OTG boost operation. Integrated with the charger, the IC supports production test mode, which provides 4.2 V at up to 2.3 A to the system. To facilitate fast system startup, the IC includes a power path circuit, which disconnects the battery from the system rail, ensuring that the system can power up quickly following a VBUS connection. The power path circuit ensures that the system rail stays up when the charger is plugged in, even if the battery is dead or shorted. The charging parameters and operating modes are programmable through an I2C Interface that operates up to 3.4 Mbps. The charger and boost regulator circuits switch at 3 MHz to minimize the size of external passive components. The FAN5404X provides battery charging in three phases: conditioning, constant current, and constant voltage. The integrated circuit automatically restarts the charge cycle when the battery falls below a voltage threshold. If the input source is removed, the IC enters a high-impedance mode blocking battery current from leaking to the input. Charge status is reported back to the host through the I2C port. Dynamic input voltage control prevents a weak adapter’s voltage from collapsing, ensuring charging capability from such adapters. The FAN5404X is available in a 25-bump, 0.4 mm pitch, WLCSP package.

• Fully Integrated, High-Efficiency Charger for Single-Cell Li-Ion and Li-Polymer Battery Packs
• Power Path Circuit Ensures Fast System Startup with a Dead Battery when VBUS is Connected
• 1.55 A Maximum Charge Current
• Float Voltage Accuracy:
  • 0.5% at 25°C
  • 1% from 0 to 125°C
  • 5% Input and Charge Current Regulation Accuracy
• Temperature-Sense Input Prevents Auto-Charging for JEITA Compliance
• Thermal Regulation and Shutdown
• 4.2 V at 2.3 A Production Test Mode
• 5 V, 500 mA Boost Mode for USB OTG
• 28 V Absolute Maximum Input Voltage
• 6 V Maximum Input Operating Voltage
• Programmable through High-Speed I2C Interface (3.4 Mb/s) with Fast Mode Plus Compatibility
  • Input Current
  • Fast-Charge / Termination Current
  • Float Voltage
  • Termination Enable
• 3 MHz Synchronous Buck PWM Controller with Wide Duty Cycle Range
• Small Footprint 1 ?H External Inductor
• Safety Timer with Reset Control
• Dynamic Input Voltage Control
• Very Low Battery Current when Charger Inactive