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javiervara's avatar
javiervara
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3 years ago
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5M570ZT144A5

We are currently using your 5M1270ZT144A5 chip, but it is currently sold out worldwide. We have been able to find the alternative 5M570ZT144A5 but this has come with a two questions/problems:
- Despite the datasheet stating the components have vertical integration and are compatible with each other, after checking the pinouts, it turns out they are not, there are two pins that are connected differently. In our design, those two pins (which with the new device should be connected to ground), are connected to one LED, and the other one is left open. The datasheet states that all the GND pins should be connected to ground, but if we want to avoid having to re-design the PCB, would it be possible to leave those two pins unconnected? (open circuit). Would this have any effect in performance of the CPLD, either in terms of speed, noise, reliability, etc.?
- The second question comes from the fact that even though our supplier (a Chinese supplier we haven't worked with before) claims he can sell us the 5M570ZT144A5 chip, I find this a bit suspicious because:
a) The device is not listed in Quartus, and thus it cannot be selected for migration device. Although I guess this shouldn't be a big problem since we can select 5M570ZT144I5, which has the same speed grade even if the temperature rating is different and it should work. Could you confirm?
b) This device is not listed (either available or unavailable) on any other of our normal supplier websites. The device is listed on both the commercial and industrial grade versions, but not the automotive one (even though the datasheet does not mention anywhere that that shouldn't be the case). Does this device actually exist?

Regards

  • AqidAyman_Altera's avatar
    AqidAyman_Altera
    3 years ago

    Hello,


    From our assessment, two GND pins which left floating should not impact the functionality of the device. However, please bear in mind this is not guaranteed by Intel as it does not follows the recommendation.


    There are possibility for the signal performance degraded and noises may be increase as well which may have a big impact for high speed signal.


    This information also might be useful for this issue: Migration Pinout


    I hope this helps you.


    Regards,

    Aqid Ayman


9 Replies

  • AqidAyman_Altera's avatar
    AqidAyman_Altera
    Icon for Regular Contributor rankRegular Contributor
    3 years ago

    Hi Javier,


    Thank you for reaching out to Intel FPGA Community.


    To answer first question, could you identify and tell us those two pins name?

    For second question, as per check, 5M570ZT144A5 is not a valid part number in Intel system.


    Regards,

    Aqid Ayman


    • javiervara's avatar
      javiervara
      Icon for New Contributor rankNew Contributor
      3 years ago

      Hi Aqid,

      Thanks for the quick response. I had not seen the reply, as the notification email had gone into the spam folder.

      I have compared side by side these two documents:

      - "Pin Information for the MAX® V 5M570Z Device - PDF Format "

      - "Pin Information for the MAX® V 5M1270Z Device - PDF Format "

      In particular for the package T144 which is the one we use. If I compare side by side the gnd and power pins of the two CPLDs I get this:

      Most pins are the same but 2 pins have changed. Pin 11 and 78 are ground in the 1270Z, but they are IOs in the 570Z. This doesn't cause us any problem, as those pins in our design would be connected to ground, thus driven as inputs. The problem is for the pins 8 and 137, which in the 1270Z are just IOs, but if we move to use the 570Z, they become grounds (thus should be connected to ground). In our PCB pin 137 is unconnected, and there is not good way to connect it to ground so we would have to leave this ground pin unconnected. Is this ok? Pin 8 is currently connected to drive an LED in our design, but we could, if necessary, replace the LED with a 0Ohm resistor so that pin would also be connected to ground as per pinout. This would mean a small change on the PCB but doable (not like the other pin). Do you recommend us to do this? If we didn't, that would mean that we would be running the 570Z, with, effectively, 2 ground pins unconnected. Would this, somehow, interfere with the normal operation of the CPLD?

      Regarding the second part. We have just received the part from this Chinese supplier and as it turns out it wasn't 5M570ZT144A5 as expected but rather 5M570ZT144C5. Could you confirm that the only automotive version of the MAXV CPLDs is for the 1270Z part? The automotive rating is important for us. I guess you can't point us to anywhere we can source the 5M1270ZT144A5 part right?

  • ak6dn's avatar
    ak6dn
    Icon for Regular Contributor rankRegular Contributor
    3 years ago

    You need to add the -N suffix for leadfree package to make a valid part number.

    So you should be looking for: 5M570ZT144A5N 5M1270ZT144A5N 5M570ZT144I5N 5M1270ZT144I5N etc

  • javiervara's avatar
    javiervara
    Icon for New Contributor rankNew Contributor
    3 years ago

    Unfortunately, I can't seem to find anywhere either the 570Z or the 240Z versions on automotive rating. The only one I can find is the 5M1270ZT144A5

  • AqidAyman_Altera's avatar
    AqidAyman_Altera
    Icon for Regular Contributor rankRegular Contributor
    3 years ago

    Hi,


    Not all pins marked as GND will be connected internally to other GND pins. Sometimes they may be left floating for package migration, or physically need to be tied to GND because they are special purpose test/mode pins.


    My suggestion is, you can check the discontinuity from pin to pin measurement on these two GND pins with other GND pins on 5M570Z. If it is connected, then it should be okay to left floating as they are connected internally. However, Intel highly recommended connecting these GND pins to the board ground plane. It is the responsibility of the designer to apply simulation results to the design to verify proper device functionality.


    Regards,

    Aqid Ayman


  • javiervara's avatar
    javiervara
    Icon for New Contributor rankNew Contributor
    3 years ago

    Hi Aqid,

    I have measured the two pins to the other grounds and they don't seem to be connected which is a bit concerning. We are testing and validating the design with the 570Z and so far it is working ok. Any idea what sort of problem/effect we could experience if that pin is left floating?.

    Regards,

  • AqidAyman_Altera's avatar
    AqidAyman_Altera
    Icon for Regular Contributor rankRegular Contributor
    3 years ago

    Hello,


    From our assessment, two GND pins which left floating should not impact the functionality of the device. However, please bear in mind this is not guaranteed by Intel as it does not follows the recommendation.


    There are possibility for the signal performance degraded and noises may be increase as well which may have a big impact for high speed signal.


    This information also might be useful for this issue: Migration Pinout


    I hope this helps you.


    Regards,

    Aqid Ayman


  • AqidAyman_Altera's avatar
    AqidAyman_Altera
    Icon for Regular Contributor rankRegular Contributor
    3 years ago

    Hi,


    I’m glad that your question has been addressed, I now transition this thread to community support. If you have a new question, feel free to open a new thread to get support from Intel experts. Otherwise, the community users will continue to help you on this thread.


    Have a nice day. Thank you.