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Altera_Forum
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15 years ago

Fitting 3C16 / 3C25 / 3C40 on same footprint

Hi,

I am trying to save some time / money by re-using one of my PCB's that was laid out for a 3C40. Can I get away with fitting a 3C16 on the same 240pin PQFP footprint?

I need far less logic in this version so can use a smaller device, but would like to avoid re-laying the PCB.

Fitting a 3C16 on the PCB laid out for the 3C40 connects some IO pins to 1.2V. The IO voltage is 3.3V.

Can I get away with doing this?

Ian.

4 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    At first glance the pin out has minor differences. The larger device has more ground and VCCINT pins which are IO pins on the smaller devices.

    I will post results when I have hardware available.
  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    Please tell us if:

    1) the pinout is the same

    2) the migration was successful

    It will help me and all the others, who will face the same problem in the future.
  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    Thanks Socrates,

    My original design was in a 3C40 but the new cut down version will fit in a 3C16. I have 3C16 and 3C25 listed as migration devices in Quartus 9.1sp2.

    Just found some documentation on the subject, think I should be ok.
  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    You have to check ALL the pins. However, I see that Quartus allows migration between 3C25 and 3C40, so I believe, that 3C16 will not fit.