The STB23N80K5 from STMicroelectronics is a MOSFET with Continous Drain Current 16 A, Drain Source Resistance 230 to 280 Milliohm, Drain Source Breakdown Voltage 800 V, Gate Source Voltage -30 to 30 V, Gate Source Threshold Voltage 3 to 5 V. Tags: Surface Mount. More details for STB23N80K5 can be seen below.