Re: 400 Mb/s ADC

Do you really need to transfer raw data? Can you do some front-end
processing to bring the speed down? If answers are 'yes' and 'no'
respectively, think of repacking. You can pack 8 bytes into one 64-bit word.
This brings the speed down to 50 MW/s, which should fit into regular 64/66
PCI.


/Mikhail



"Jeff Peterson" <[EMAIL PROTECTED]> wrote in message
news:[EMAIL PROTECTED]
> We are building a new radio telescope called PAST
> (http://astrophysics.phys.cmu.edu/~jbp/past6.pdf)
> which we will install at the South Pole or in Western China.
>
> To make this work, will need to sample (6 to 8 bit precision) dozens
> of analog voltages at 400 Msample/sec and feed these data streams into
> PCs. One PC per sampler.
>
> The flash ADCs we need are available (Maxim), but we are finding it
> difficult to get the data into the PC.
>
> One simple way would be to use SCSI ultra640, but so far I have not
> found any 640 adapters on the market.  Is any 640 adapter available?
> anything coming soon?
>
> or we could go right into a PCI-X bus.  has anyone out there
> done this at 400 Mb/s?  is this hard to do? FPGA core liscense
> for this seems expensive ($9K), with no guarentee of 400 mByte rates.
>
> is there a better way?
>
> thanks
>
> -Jeff Peterson