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Altera_Forum's avatar
Altera_Forum
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15 years ago

MaxII with 5V TTL Compatibility

Hi all,

I am planning to migrate my CPLD design from Lattice series to Altera MAXII series. The only problem I am having at the moment in selecting device is 5V I/O TTL Compatibility. Lattice device are very much 5V TTL Compatible but Altera MAXII did not mention it clearly. The data-sheet tell that EPM1270 and EPM2210 at 3.3V can support 5V TTL I/O. I just wanted bit more details in this if possible.

Regards,

Hitesh

2 Replies

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    15 years ago

    I think, the datasheet is clear in this regard. MAX II isn't 5V tolerant, you have to use voltage clamps or similar means to use it with 5V logic level. See Table 2.7, MAX II MultiVolt I/O Support. Devices that compare with Lattice CPLD are e.g. Altera MAX3000.

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    15 years ago

    Dear FvM,

    Thanks for the reply. I agree with you up to certain extent but if I see the data sheet it will tell me some different stories. if you open the below link and see the page number 2-32 in chapter 2, it clearly mention there that EPM1270 and EPM2210 devices support 5V TTL Logic.

    altera.com/literature/hb/max2/max2_mii5v1_01.pdf

    Will wait for your prompt feedback.

    cheers

    Hitesh