ADP2323ACPZ ripples at output

Hi , 

I am using ADP2323ACPZ for generating 3.3V & 1.2 V . 3.3V is genrating perfectrly however i am getting ripples at output . I am attaching the schematic & output waveform. since there is lot of ripple the FPGA is unable to boot through any mode. 

Gaurav 

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    •  Analog Employees 
    on Nov 26, 2019 8:16 AM in reply to gauravvalecha

    C112, C117 and C120 perform the large load for the output of the ADP2323. During soft start, it requires large input current to charge those capacitors to Vout within the soft start time. If the soft start time is too short, the charging current may trigger high-side OCP, which results in failure of the start up.

    What does the input 5V come from? power supply? another regulator? Does this 5V have enough load capability?

    If we increase soft start time of both power rails of the ADP2323, does this issue go away?

    Thanks!

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