[Cryptech Tech] Alpha board strategy

[Павел Шатов]

On 19.02.2015 14:45, Joachim Strömbergson wrote:
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> Aloha!
>
> Шатов Павел wrote:
>> I want to add two more FPGA families to our discussion. The first
>> family is Cyclone-IV from Altera. All of its members are available in
>> the free Quartus license. The second family is Artix-7 from Xilinx.
>> All of its members are available in the free ISE license too. I've
>> updated FPGA table, green items are available using free licenses,
>> yellow ones require subscription licenses. There's a very good point
>> in the possible risks list, which is taking too long to decide on
>> what to have in our Alpha Board. So let's select an FPGA at first.
> (Your probably didn't see my FPGA survey that I posted before Christmas
> or so.) Good table.

After I joined this project in December, I read December and November 
tech archive. I must have missed this survey, I'm sorry.

> The Cyclone-IV is manufactured in an older technology that is slower
> than Cyclone-V. The biggest Cyclone-IV is as big as the biggest
> Cyclone-V that we can build with free tools (A7). Thus selecting
> Cyclone-IV over Cyclone-V would only remove the possibility of adding
> more headroom by buying tools. Also, if you look at pricing, Cyclone-IV
> is not really cheaper than Cyclone-V.
That is exactly what I wanted to say. Largest Cyclone-IV is larger than 
largest "free" Cyclone-V. Maybe this will be enough and we won't have to 
buy development tools.

> The Artix-7 is much more interesting since it would give much more
> headroom. I have not been able to dig up good prices for Artix-7,
> neither 100T or 200T. Do you have any estimates? It seems that the only
> devices available in Artix-7 is 100T and 200T which makes any reduction
> in size harder to do. But that is no big issue.
>
Artix-7 is relatively new (as is Cyclone-V). As far as I remember, at 
the time it was launched, only two largest chips in the family were 
available (100T and 200T). I believe that smaller chips should now be 
available too. I've taken prices for my table from Digi-Key:
http://www.digikey.com/product-detail/en/XC7A100T-1FGG484C/122-1885-ND/3925804
http://www.digikey.com/product-detail/en/XC7A200T-1FBG484C/122-1871-ND/3925796