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NM11's avatar
NM11
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2 years ago

Power Sequence of Arria V GX (FPGA)

We are using Arria V GX (FPGA) in a prototype we are considering developing. I have 3 technical questions about Power Sequence. 1. In the Arria V Device Datasheet, at the end of Table 3 of 1.1....
lixy's avatar
lixy
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2 years ago

Hi Naoki,

​

Sorry for late response. I was confirming the problem with more senior engineers. Here's our answer.


According to the waveform and description you provided, the "slight drop" is possibly the "IR Drop" caused by reference floating, which means it could be only a measurement error. Another possibility could be that the Voltage Regulator‘s output efficiency is not high enough. Therefore you may not need to worry about this "slight drop".


However, there could be another potential problem that the "VCC_0V75" does not seem to start from GND. Please also check this to make sure this power rail is not affected by other power supplies.


Regarding to the problem that how "non-monotonic power supply" will affect the FPGA, we still do not have an clear answer though.


Thanks & Regards,

Xiaoyan


NM11's avatar
NM11
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2 years ago

Hi Xiaoyan-san,

Thank you for your answer.

I will check the "VCC_0V75".

Please continue to confirm the influence of "non-monotonic power supply".
Please also consider the following as described on April 5
> So we intend to set the power supply from our system to the FPGA as specified.

Best Regards,

Naoki

  • NM11's avatar
    NM11
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    2 years ago

    Hi Xiaoyan-san,

    I checked the "VCC_0V75".

    This power rail is not connected to other power supplies on schematic.
    The cause of the floating from GND was that this power rail was taking a long time to discharge (about 1 minute).
    When I turn on the system before the power rail finishes discharging, the voltage rises from about 0.2V.
    Is there a problem with a maximum of about 0.2V?
    The system appears to be working fine in that case.

    So, this power rail is not affected by other power supplies.

    I would also appreciate your response to the following questions I have asked you in the past.
    > Please continue to confirm the influence of "non-monotonic power supply".
    > Please also consider the following as described on April 5
    >> So we intend to set the power supply from our system to the FPGA as specified.

    Best Regards,

    Naoki