The Si4178DY from Vishay is a MOSFET with Continous Drain Current 12 A, Drain Source Resistance 17 to 33 milliohm, Drain Source Breakdown Voltage 30 V, Gate Source Voltage -25 to 25 V, Gate Source Threshold Voltage 1.4 to 2.8 V. Tags: Surface Mount. More details for Si4178DY can be seen below.