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1V Power supply under-powered

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What's the maximum power that can by drawn by the Zynq PL? Has this been tested?

I have build a large design (80%) that need to runs at 100MHz, but when I program the bitstream to the Zedboard. The Zynq reset a few ms after being DONE.

Also, I have probed the 1V power supply at C357. After, the PL is DONE, the voltage go down to about 560mV and go back up to 1V probably because the PL resets.

What could be causing this?

Is it because the PL draw to much power?

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    Hey everybody,

    I've been talking with Bryan about the power issue and wanted to make a suggestion to the community if you are looking to design your own ZedBoard.  The two outputs of the MAX15021 are capable of 4A and 2A respectively.  In our design we had the 1.5V used to power the DDR running off of LX1 (the 4A output).  Our estimations show that the max expected current draw on the 1.5V rail is 1.5A.  That means that the 2A LX2 output should be sufficient to provide the current needed for the memory.

    If you design your own board, use the 1uH inductor from the 1.5V supply and just swap the circuits for 1V to the LX1 output and for 1.5V to the LX2 output.  You'll notice that all the components are the same except for the feedback set resistors and the inductor.  You'll need to use the larger current rated inductor on the 1V supply as well, but other than that there are minimal changes.

    In the meantime, if anyone who has had this issue would be willing to share their ZedBoard design and their XPE output with us it would be greatly appreciated.  I'd like to work with these data points to try and determine where the disconnect is between the tool and the actual current draw.  I'd like to go back to Xilinx to discuss what we've seen, but I need to be able to reproduce the scenario on my bench to be able to accurately describe the problem.
    Thanks
    Chris

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    Hey everybody,

    I've been talking with Bryan about the power issue and wanted to make a suggestion to the community if you are looking to design your own ZedBoard.  The two outputs of the MAX15021 are capable of 4A and 2A respectively.  In our design we had the 1.5V used to power the DDR running off of LX1 (the 4A output).  Our estimations show that the max expected current draw on the 1.5V rail is 1.5A.  That means that the 2A LX2 output should be sufficient to provide the current needed for the memory.

    If you design your own board, use the 1uH inductor from the 1.5V supply and just swap the circuits for 1V to the LX1 output and for 1.5V to the LX2 output.  You'll notice that all the components are the same except for the feedback set resistors and the inductor.  You'll need to use the larger current rated inductor on the 1V supply as well, but other than that there are minimal changes.

    In the meantime, if anyone who has had this issue would be willing to share their ZedBoard design and their XPE output with us it would be greatly appreciated.  I'd like to work with these data points to try and determine where the disconnect is between the tool and the actual current draw.  I'd like to go back to Xilinx to discuss what we've seen, but I need to be able to reproduce the scenario on my bench to be able to accurately describe the problem.
    Thanks
    Chris

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