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KrishnamRaju's avatar
KrishnamRaju
Icon for New Contributor rankNew Contributor
2 years ago
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MAXII to MAX5 CPLD foot print compatability

Dear Team We are chaning MAX CPLD II EPM2210F256C5N with MAX V CPLD 5M2210ZF256I5N . 1. Are both CLPDs foot print compatiable? 2. In my old design for MAXII VCCINT 3.3V is there and Now I am chang...
Programmable Logic Device
  • FvM's avatar
    FvM
    2 years ago

    Hi,
    It's all described in device handbook and datasheet.

    GPIO have weak pull-up resistors to respective VCCIO until user mode becomes active. State of unused pins can be globally selected in Quartus device and pin options.

    "Reserves all unused pins on the target device in one of 5 states: as inputs that are tri-stated, as outputs that drive ground, as outputs that drive an unspecified signal, as input tri-stated with bus-hold, or as input tri-stated with weak pull-up."

    Personally, I won't choose high-Z without pull-up if there are any unconnected GPIO pins because floating inputs can involve additional device current consumption.

    Regards
    Frank

FvM's avatar
FvM
Icon for Super Contributor rankSuper Contributor
2 years ago
@KrishnamRaju wrote:

I found a T6 pin which is ground in MAX V is I/O in MAX II.

So you found that the devices are not 100 % pin-compatible. I guess, there's a reason why T6 is now assigned to ground, but knowing it won't help you much. If T6 is used as IO in your MAX II design, you need to modify the PCB.