The MMSZ4683 from Micro Commercial Components is a Zener Diode with Zener Voltage 3 to 3.15 V, Zener Current 50 mA(zener test current), Voltage Forward 0.95 V, Current Reverse Leakage Current:- 0.8 uA, Power 500 mW. More details for MMSZ4683 can be seen below.