The Si5948DU from Vishay is a MOSFET with Continous Drain Current 4 A, Drain Source Resistance 65 to 94 Milliohm, Drain Source Breakdown Voltage 40 V, Gate Source Voltage -20 to 20 V, Gate Source Threshold Voltage 1 to 2.5 V. Tags: Surface Mount. More details for Si5948DU can be seen below.