The BP3621 from ROHM Semiconductor is a Wireless Charging Transmitter with Voltage 0.4 to 5.5, Input Voltage Range 0.3 to 0.7 V, Output Current 160 mA, Switching Frequency 13.56 MHz, Operating Temperature -10 to 50 Degree C. Tags: Surface Mount. More details for BP3621 can be seen below.