The Si4948BEY from Vishay is a MOSFET with Continous Drain Current 3.1 A, Drain Source Resistance 100 to 150 milliohm, Drain Source Breakdown Voltage -60 V, Gate Source Voltage -20 to 20 V, Gate Source Threshold Voltage -1 to -3 V. Tags: Surface Mount. More details for Si4948BEY can be seen below.