[Cryptech Tech] Speed grade for the Arix-7?

[Павел Шатов]

On 16.03.2015 17:52, Joachim Strömbergson wrote:
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> Aloha!
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> What speed grade do you recommend for the Artix-7?

Well, Xilinx offers two speed grades for commercial FPGAs, these are -1 
and -2. Lower number is slower and cheaper.

We can't predict what speed grade will suit us at this stage, because we 
don't have all the cores yet. We can't compile them to estimate their 
timing requirements. In this situation the common approach is to use 
faster (-2) chip on the first small batch of boards. After you make sure 
that these boards are actually working and singing something, you change 
target FPGA in ISE to a slower one (-1) and try to re-compile your 
project. If you don't get any timing errors, than you can buy slower 
chip for the following batch of boards.

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With best regards,
Pavel Shatov