The BT139X-600F is a triac, 600V, 4A offered by NXP Semiconductors. It is a high-performance, high-quality, insulated gate bipolar transistor (IGBT) with an integrated high voltage power diode. This device it ideal for use as a general purpose switch in a wide range of AC power control applications, including lighting, heater control, heat pump, air conditioner, and appliance control. It has a low forward voltage drop and fast turn-on response time which make it suitable for high power applications. The device also features an integrated over temperature protection (OTP), over voltage protection (OVP) and current sense circuit (CSC). It is halogen-free, RoHS compliant and UL certified.