The TISP4180M3AJ from Bourns is a Silicon Controlled Rectifier with Breakover Voltage 180 V, Breakover Current 0.6 A, Gate Trigger Voltage 145 V, Gate Trigger Current 23 A, Temperature Operating Range -40 to 85 Degree C. Tags: Surface Mount. More details for TISP4180M3AJ can be seen below.