The MSM1312 from Massachusetts Bay Technologies is a RF Schottky Diode with Peak Reverse Voltage 5 V (Breakdown Voltage), Forward continuous Current 1 to 5 mA, Forward Voltage 0.400 V, Power Dissipation 250 mW, Capacitance 0.14 pF. Tags: Chip. More details for MSM1312 can be seen below.