USB-Compliant Single-Cell Li-Ion Switching Charger with USB-OTG Boost Regulator

The FAN54015 IC provides a fully integrated charging function from a USB power source for single-cell (1S) Li-Ion and Li-Po batteries. The IC includes over-voltage protection, a highly efficient DC-DC synchronous converter with a 1.45 A output at 4.2 V, sufficient to charge up to 2000 mAh Li-Ion and Li-Po batteries at 0.7 C charge rate. The FAN54015 provides battery charging in three phases: conditioning, constant current, and constant voltage to protect the battery and maximize runtime. Charge current is reduced if the on-chip die temperature monitor reaches 120°C. The device is I2C controlled for programming charge operating modes and parameters. The IC is offered in a 1.96 mm x 1.87 mm 20-bump WLCSP.