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Altera_Forum
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11 years ago

5CEFA9F23 is OK if CORE_VCC = 1.18?

I use 5CEFA9F23 .The VCC(Core voltage) of board is 1.18V ，so i want to know whether the 5CEFA9F23 works properly？

And i use jtag to connect FPGA ,i found idcode is 2BFC0DD, so i want to know whether the 5CEFA9F23 is bad when vcc is 1.18V?

thank you!

4 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    11 years ago

    1.18 V is above the maximum of 1.13 V but below the absolute maximum of 1.43V

    Basically it should not damage the device at 1.18 V, but it's not in spec either, so all the functional timings are outside the range of characterization.

    I would fix the core voltage and try the IDCODE again.

    The Value you are reading, I'm not seeing in the table 9-1 of the handbook. I'm reading the code should be 02B140DD for the 5CEFA9 device.

    Pete
  • Altera_Forum's avatar
    Altera_Forum
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    11 years ago

    Hi,

    I agreed with Anakha's comment here, it is recommended to operate the device within the recommended spec.

    The IDCODE is unique for each Cyclone V device which can be identified in a JTAG chain but the IDCODE that you observed cant be found from the list of Cyclone V devices
  • Altera_Forum's avatar
    Altera_Forum
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    11 years ago

    Hi,

    From what I know, is best to follow the spec as this will also affects your timing model.
  • Altera_Forum's avatar
    Altera_Forum
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    11 years ago

    Hi,

    Just to add on that since it is exceeding the specs, there might be risk ie reduced life span of your device in the long run even though it might not damage the device instantly.