FMMT411FDBWQ Low Voltage Avalanche Transistor Diodes Incorporated FMMT411FDBWQ Low Voltage Avalanche Transistor is a silicon planar bipolar transistor designed for operating in avalanche mode. Tight process control and low inductance packaging produce high-on-current pulses with fast edges. This Diodes Incorporated Bipolar Junction Transistor (BJT) is designed to meet the stringent requirements of automotive applications.