The turn-on transition has three timing components: drain-current turn-on delay time, turn-on delay time, and turn-on rise time. The drain-current turn-on delay time is from when IN goes high to when the GaN FET drain-current reaches 1A. The turn-on delay time is from when IN goes high to when the drain-source voltage falls 20% below the bus voltage. Finally, the turn-on rise time is from when drain-source voltage falls 20% below the bus voltage to when the drain-source voltage falls 80% below the bus voltage. Note that the turn-on rise time is the same as the V_DS 80% to 20% fall time. All three turn-on timing components are a function of the RDRV pin setting.