Using a current trigger will turn this triac L4004L3 thyristor manufactured from Littelfuse on and applying a forward-biased voltage to it will keep it on. This device has a surge current rating of 40 A. Its repetitive peak forward blocking voltage is 400 V, while its repetitive peak reverse voltage is 400 V. This SCR thyristor has a minimum operating temperature of -40 °C and a maximum of 110 °C.