The AAT3221IJS-1.6-T1 from Skyworks Solutions is a LDO Voltage Regulator with Input Voltage 1.83 to 5.5 V, Output Voltage 1.5 to 3.5 V, Dropout Voltage 230 mV, Output Current 0.15 A, Quiescent Current 0.0011 mA. Tags: Surface Mount. More details for AAT3221IJS-1.6-T1 can be seen below.