The slope of the drain-source voltage change is related to the value of R3*C2. For a system with a constant load, as long as the value of R3*C2 is controlled, the rising slope of the hot-swap inrush current can be controlled.
In the 0~t1 stage, the Schottky diode D2 has not been turned on, so Vgs is equal to 0. During this period, the -48V power supply charges C2 through R3 and R5, and when the voltage of C2 rises to the turn-on voltage of D2, the MOS tube When the gate-source voltage rises to the turn-on voltage Vth of the MOS tube, the MOS tube is turned on, and the drain-source current Ids begins to increase, and when the gate-source voltage of the MOS tube rises to the platform voltage Vplt , the drain-source current Ids also reaches the maximum. At this time, the drain-source voltage Vds enters saturation and begins to decrease. When the platform voltage Vplt ends, the MOS transistor is completely turned on, the drain-source voltage is reduced to the lowest level, and the on-resistance Rds of the MOS transistor is the smallest.