1. sgonzalez90

    Thread Starter New Member

    Feb 5, 2014
    Currently replacing a Xilinx FPGA on a board, due to obsolescence...Never had to replace an FPGA design before. I was recommended to select an altera Cyclone IV/V for my application. What I really need to know are these proper definitions:

    LE- Logical elements/Logic Cells?
    Embedded Memory- is this total RAM bits? or block ram bits?
    Looking at the previous datasheet, I did not find info on Max n X m multipliers
    Transceiver channels-also were not in my sheet
    LVDS Transmit Channels- also were not in my sheet

    I just need a valid resource. I have taken a graduate course in Verilog/VHDL, but never done a full project, pointers?
  2. Papabravo


    Feb 24, 2006
    You might be better off doing the design from scratch. It is unlikely in the extreme that you will be able to continue using the existing PCB. The most likely reason is that newer chips will need a different array of power supplies.

    From a time perspective you will get there faster by understanding the requirements and debugging something you understand rather than trying to understand something and then trying to replicate it - bugs and all.
  3. kubeek

    AAC Fanatic!

    Sep 20, 2005
    From the fact that you´re replacing an obsolete part I expect you have the original source codes. So why not try the respective Xilinx and Altera IDEs and see into which devices the design fits? That should save you a lot of time going through the datasheets and trying to compare apples with oranges, as I don´t think that different architectures will be readily comparable.
  4. ErnieM

    AAC Fanatic!

    Apr 24, 2011
    Give a call to your local service rep. They can at times be surprisingly helpful.
  5. Brownout

    Well-Known Member

    Jan 10, 2012
    LE - this vaires from vendor to vendor. This is a physical combination of logical elements, and typically includes logic to connect to long data lines and other LE's, a lookup table, a flip-flop and support logic.

    Embedded Memory - yes this is block RAM. You can also use the small memory in the LE as distributed RAM.