The 1SMA5931BT3G from onsemi is a Power Diode with Forward Current 0.0208 A, Forward Voltage 17.1 to 18.9 V, Reverse Current 0.5 uA, Reverse Voltage 13.7 V, Repetitive Peak Reverse Voltage 13.7 V. Tags: Surface Mount. More details for 1SMA5931BT3G can be seen below.