The TPS6206x has an internal soft start circuit that controls the ramp up of the output voltage. Once the converter is enabled and the input voltage is above the undervoltage lockout threshold V_UVLO the output voltage ramps up from 5% to 95% of its nominal value within t_Ramp of typically 250 µs.

This limits the inrush current in the converter during start-up and prevents possible input voltage drops when a battery or high impedance power source is used.

During soft start, the switch current limit is reduced to 1/3 of its nominal value I_LIMF until the output voltage reaches 1/3 of its nominal value. Once the output voltage trips this threshold, the device operates with its nominal current limit I_LIMF.