onsemi FAN54300UCX

The FAN54300 combines two highly integrated switch - mode chargers and a boost regulator to minimize single - cell Li - Ion charging time from a USB and/or auxiliary power source. Charging parameters and operating modes are programmable through an I²C Bus interface that operates up to 3.4 Mbps. The charger and boost regulator circuits switch at 3 MHz to minimize the size of the external passive components. The FAN54300 provides battery charging in three phases: conditioning, constant current, and constant voltage. To ensure USB compliance and minimize charging time, the USB input current is limited to the value set through the I²C host. Charge termination is determined by a programmable minimum current level. A safety timer with reset control provides a safety backup for the host. The IC automatically restarts the charge cycle when the battery falls below an internal threshold. If the input source is removed, the IC enters a high - impedance mode, with leakage from the battery to the input prevented. Charge status is reported back to the host through the I²C port. Charge current is reduced when the die temperature reaches 120°C. The FAN54300 can operate as a boost regulator on command from the system. The boost regulator includes a soft - start that limits inrush current from the battery. The FAN54300 is available in a 30 - bump, 0.4 mm pitch, wafer - level, chip - scale package (WLCSP).

• Fully Integrated, High - Efficiency Charger for Single - Cell Li - Ion and Li - Polymer Battery Packs
• Accepts USB or Dedicated Power Input Source 5 V, 300 mA Boost Mode for USB OTG from 2.5 to 4.5 V Battery Input
• Charge Voltage Accuracy: ±0.5% at TA = 25°C, ±1% from TA = 0 to 125°C
• ±5% USB Input Current Regulation Accuracy
• ±5% Charge Current Regulation Accuracy
• 20 V Absolute Maximum Input Voltage
• 9.5 V Maximum Input Operating Voltage on VIN Pin, 6.5 V Maximum on VBUS Pin
• Up to 1.5 A Maximum Charge Rate
• Programmable Charge and Mode through High - Speed I²C Interface (3.4 Mb/s) with Fast Mode Plus Compatibility
• Input Current, Fast - Charge / Termination Current, Charger Voltage, Safety Timer, Termination Enable
• 3 MHz Synchronous Buck PWM Controller with Wide Duty Cycle Range
• Small Footprint, 1 μH, External Inductors
• Safety Timer with Reset Control
• Weak Input Sources Accommodated by Reducing Charging Current to Maintain Minimum VBUS Voltage
• Low Reverse Leakage from Battery Drain to VBUS or VIN
• Register and Slave Addresses Compatible with FAN540X and FAN542X Families

• Cell Phones, Smart Phones, PDAs
• Digital Cameras
• Portable Media Players