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Interfacing with lots of ADCs using LVDS

I need to process up to 24 ADCs, each running at 5-10MSPS. Each ADC needs to have 12 bit resolution, and the ADCs are spread over 3 PCBs. The AD9220ARS would do as a good economical 12bit ADC, but interconnecting 24 of them looks ugly. Quad or octal devices might be a way forward, but has anyone tried using LVDS interfaces to get the sheer number of interconnects down?

  • Hi OliverSedlacek-

    Thanks for being an EngineerZone member.  EngineerZone currently provides communities that support developers using Analog Devices Amplifiers, Direct Digital Synthesis, Analog Microcontrollers, RF Components, Embedded Processors and DSPs, and Video products.

    We are planning to add communities that cover other ADI products over time, but currently are unable to answer questions about these products, such as the ADC you mention, on EngineerZone.  I would suggest submitting your question to the Analog Devices support team in your region.  You can find the appropriate support contact on our website at: http://www.analog.com/support.

    Regards,
    AndyR
    EngineerZone Community Manager

  • Hi AndyR,

    it seems, that I have the same problem, because I like to develop a 8-16 ch Digitizer in the size of Handheld or Smarttphone and in the News

    http://www.analog.com/en/press-release/11_10_11_Highspeed_ADConvert_Feature_More_Channels/press.html

    I have found the Killer:

        AD9637:   Octal, 12-Bit, 40/80 MSPS Serial LVDS 1.8 V A/D Converter

    :-D  which is realy what I like to use, uhm, 40 MSPS are enough for me!  :-D

    Unfortunately I have no clue, how to handel 8 or 16 LVDS channels...  I was searching the Website and the Internet for App Notes or Design References but have found nothing

    OK, I like to use a bigger ARM Cortex A9 (1000MHz Dual or Singel-Core) for it, which has PCIe capabilities.

    Time to create a Forum Group vor the LVDS Stuff

    Greetings

    Michelle

    P.S.:  I have studies while I was in the french Army and something like a Maintenance Engineer, which mean, I have lost more then 10 years in the Army and now since more then 4 years I am out and have to re-learn all from scratch!  --  Not very funny!

  • Hi Michelle-

    We do now have a High Speed ADCs community on EngineerZone at: http://ez.analog.com/community/data_converters/high-speed_adcs, so you may be able to get some answers there.

    Andy

  • Michelle,

    I don't see any processor being able to handle 40 MSPS times 16 channels, which I make to be 640 MSPS - 960 MBytes/sec 7.6 GBits/sec. If on the other hand you are looking at an FPGA to handle the data, both Altera and Xilinx chips have LVDS capability.

    For my project I ended up using dual 14 bit ADCs, with four ADCs connected to each FPGA. Each ADC is connected through a parallel bus, so I needed 56 data pins plus a few clock and phase lines. The buses run at 20 MHz so that I can get the both ADC channels across when sampling at 10 MSPS.

  • There is something what I realy find confusing:

    Some manufacturers use MSPS for all ADCs together and others MSPS/Channel

    From your message I see, you understood 40 MSPS/Channel  :-D  which would kill anything

    Ehm no, I need two solutions with:

    1)  8-16 channels (8bit would be OK) of 2-3 MSPS/Channel

    2)  2 Very-High-Speed ADs with >200 MSPS/Channel + 1 Trigger signal

    First will be a Digital Analyzer and the seond one an OpenSource DSO

    And yes, I will look ito this FPGA stuff, but I have never used it, which mean, I need very much time.

    Greetings

    Michelle

  • Hi,

    I have moved this thread from the Processors and DSP category to the high-speed ADC community. As Andy suggested above, you are more likely to get answers here. Please continue the discussion here.

    Regards,

    Craig.

  • Michelle,

    I'd still look at FPGAs to implement your DSP logic. Dedicated DSPs are now targeted at specific applications (e.g. audio compression, hi-fi processing), and as soon as you want to do something a bit unusual they become a bit cumbersome. You can tuck a soft core processor into them if you still need to execute some C code.

  • Hi,

    We use a Virtex4 FPGA from Xilinx to capture the data of the AD9637.  These octal ADCs are used in systems where the channel count can be very high, such as 256 channel ultrasound systems, and FPGA or dedicated ASICs are the usual solution.

    Good luck with your design,

    David