[Moved] CPLDs and FPGAs contain embedded memory

[pumperthruster]

I am designing a new circuit that samples an input signal from 1Mhz to 6Mhz(0-1 volt sinusiod). I will use a fast 12bit ADC to capture this signal at 20Mhz. The ADC has a parallel output. I am deciding whether to use either an FPGA or CPLD to grab one single data chunk from the ADC(its a one shot device), lets say the first 8K samples, then do an FFT or even simpler calculation on the stored data. Depending on the result of this calculation, the devise should output a 1 or a 0. That's it. Price is critical. This whole process gets repeated every minute or so.
So. question.
1) Do FPGA's or CPLD's have embedded sram. (this would save me adding a separate sram chip). I'd need at least 8Kx8 (64Kb)minimum. That gives me 8000 byte samples (less for 12bit of coarse)
2) What's the cheapest device out there to do the job, any recommendations?
3) for this application, do I go for CPLD or FPGA? (Note, cost is critical, and ease of design too, I'm no wizard when it comes to programming these devices - in fact I have yet to learn)

Ferd.

 

[chipseller]

Re: CPLDs and FPGAs contain embedded memory

Hi Ferd
Nearly all modern FPGA have embedded SRAM, which can be configured as SRAM, FIFO or DPRAM and 8kB is not a huge amount. Nearly all vendors should be able to provide a device which offers both the storage and performance at a relatively low cost. CPLDs do not contain RAM
I cannot say which will be the cheapest as it all depends on quantity, but, again, it really depends on your budget. I suspect tha Lattice or Microsemi probably offer the devices best suited to your needs as they have non-volatile solutions. You can get the Microsemi pricing from the Avnet website and Lattice from MSC.
I would go with an FPGA here as it will offer you on-chip storage and lower power and greater flexibility of design, especially if you do put an FFT in there. A CPLD probably would not be able to cope with something that complex
Good luck

 

[TrickyDicky]

From altera you want the cyclone series. They have plenty of onboard ram and embedded multipliers for your FFT.
Xilinx would be the spartan or artix series.