The Si3440ADV from Vishay is a MOSFET with Continous Drain Current 2.2 A, Drain Source Resistance 316 to 432 milliohm, Drain Source Breakdown Voltage 150 V, Gate Source Voltage -20 to 20 V, Gate Source Threshold Voltage 2 to 4 V. Tags: Surface Mount. More details for Si3440ADV can be seen below.