7.1.2 Turn-off Delays

The timing of the turn-off transition has three components: propagation delay, turn-off delay, and fall time. The first component is the propagation delay of the driver from when the input goes low to when the GaN FET starts turning off (represented by the drain rising above 10 V). The turn-off delay is the delay from when the FET starts turning off to when the drain voltage swings up by 20 percent. Finally, the fall time is the time it takes the drain voltage to slew between 20 percent and 80 percent of the bus voltage. The turn-off delays of the LMG341xR050 are independent of the drive-strength resistor but the turn-off delay and the fall time are heavily dependent on the load current.