The TYN1225 from STMicroelectronics is a Silicon Controlled Rectifier with Breakover Voltage 1200 V, Breakover Current 300 A, Gate Trigger Voltage 1.3 V, Gate Trigger Current 0.04 A, Temperature Operating Range -40 to 125 Degree C. Tags: Through Hole. More details for TYN1225 can be seen below.