The TPS1685x implements insertion delay at start-up to ensure the supply has stabilized before the device tries to turn on. This is to prevent any unexpected behavior in the system if the device tries to turn on while the card has not made firm contact with the backplane or if there’s any supply ringing/oscillation during startup.

The device initially waits for the VDD supply to rise above the UVP threshold and all the internal bias voltages to settle. After that, it remains off for an additional delay of 10 ms irrespective of the EN/UVLO pin condition.