• State Resolved
  • Locked Locked
  • Replies 9 replies
  • Answers 3 answers
  • Subscribers 47 subscribers
  • Views 822 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

ADS9817: ADS9817's sample rate

l cj
Prodigy 10 points
Part Number: ADS9817
Other Parts Discussed in Thread: ADS9813, MUX36D08, ADS9120

Tool/software:

it's about ADS9817's sample rate.

In ADS9817's datasheet, there is saying "This overall system can achieve a maximum throughput of 2 MSPS/channel for all channels", but its block diagram shows that there are 2 multiplexers for ADC A&ADC B respectively.

I need to confirm that if ADS9817's ALL 8 Channels could achieve 2MHz sampling rate simultaneously? In other words, If ADS9817 could output 16MHz data when enabling all 8 channels?

If so, every 4ch in each group are not simultaneously sampling?

And more, ADS9813 seems perfect for 8 channels with 2MHz  simultaneously sampling, when could it be published?

Thanks a lot.

  • 0
    TI__Expert 8936 points

    Hi,

    Thanks for your question! There are two ADC cores in ADS9817, so 2 channels are sampled simultaneously at a time. So, channel 1 in ADC A and channel 8 in ADC B would be sampled simultaneously at 2MSPS/channel, and then channel 2 in ADC A and channel 7 in ADC B, and so on. All 8 channels are always enabled.

    The ADS9813 would sample all 8 channels simultaneously at 2MSPS/channel. It has already been released, please see the product folder here.

    What is the application you are hoping to use this ADC in?

    Best regards,

    Samiha

  • 0 in reply to Samiha Sharif
    Prodigy 10 points

    hi,Samiha

         Thanks for your reply!

         I'd like to double check: 8MSPS is the actual total sample rate for each ADC core? If take the internal structure as a black box, the ADS 9817 would output 16M samples (2M samples for each channel,regardless of the simultaneously sampling issue) in one second, am i right?

        As for ADS9813, i keep watching it for many days, and i've seen its datasheet from ti.com. But its release state was always PREVIEW and i can't purchase or even request a Sample.  Nobody could give me an estimated officially release date.

       I take the ADS9813 as my best choice for my DAQ application(2MS/s/ch as required), and if it's still not released for purchasing in one month, the ADS9817 would be the only choice for me.

  • 0 in reply to l cj
    TI__Expert 8936 points

    Hi CJ,

    Yes, each ADS9817 core is capable of 8MSPS, but since each core is mux-ing through 4 channels, the ADCores are sampling 2M samples per second. There is a soon-to-be-released variant device, where each core has only one channel and samples at 8MSPS. But this device only has 2 channels total. Please let me know if that would be appealing.

    You should be able to order the ADS9813 devices through the product page here, after you sign in with your myTI account. Does this page not populate for you?

    How many devices are you needing, and by when? We plan to fully release the device by ~September, but you should be able to order devices now. Please let me know if you continue to face issues with ordering.

    To better understand your use case, is your DAQ system part of tester equipment?

    Best regards,

    Samiha

  • 0 in reply to Samiha Sharif
    Prodigy 10 points

    hi,Samiha

    the ADCores are sampling 2M samples per second(per channel or total 4 chs?)

    Based on your explanation, although ADS9817 core is capable of 8MSPS, but it's actualy working at 2MSPS? and the ADS9817 is outputting 4M samples per second? If so, i do need ADS9813 for 16MSPS total throughput per second.

    The new ADC at 8MSPS is turely appealing to us!

    I logged in and the web page of ADS9813 ordering keeps showing Out of Stock no matter of ti.com or ti.com.cn

    My DAQ Board is a standalone system that consists of ARM+FPGA+ADC, similar with NI's sbRIO; This board aims to apply in the electricity grid field to build a large sacle distributed DAQ system.

    Our team formly used OP+MUX36D08/ADG506+ADS9120, but the MUX36D08/ADG506 is too sensitive to temperature and we have to use cooling fan. Further more, the multi-channel linearity and consistency is not very satisfied that causes very hard calibration work.

    ADS9817&ADS9813 is some kind of all-in-one architecture that is appealing so much to us. When noticed ADS9813, we don't hesitate with one second to upgrade with it.

    In the electricicy grid so-big field in china, we need 1k devices a year at least.

    In the coming 3 months, we'll focus on developing 2 test boards using 6 picecs(24ch per board) of ADS9813. We must finish the whole debug work by September.

    It's very appreciated if you can reach out and help slove the ordering issue.

  • 0 in reply to l cj
    TI__Expert 8936 points

    Hi CJ,

    Thanks for the detail! Yes, it sounds like the ADS9813 would be a better fit for you as that ADC simultaneously samples all 8 channels. 

    Would the 8 MSPS ADC be useful in this same application or in another project?

    We have contacted the TI Store about the "out of stock" status you are seeing. I will update you early next week about the ordering error. We will resolve this issue. 

    In the meantime, we also have a ADS9813 evaluation module (EVM), which can be interfaced with our FPGA controller card, TSWDC155EVM. Please feel free to order the EVM if it will help your debug. We also have some FPGA interface example code for this ADC that you may find useful.

    Best regards,

    Samiha

  • 0 in reply to Samiha Sharif
    Prodigy 10 points

    hi Samiha,

    The 8 MSPS ADC is useful in my another project that actually requires ~5MSPS rate.

    Is there any updates on the ADS9813 ordering issue? It's still showing "out of stock" in the TI Store.

    We're eager to order several ADS9813 chips.

    Thanks for your help!

  • 0 in reply to l cj
    TI__Expert 8936 points

    Hi CJ,

    Understood. What kind of application is the other project that needs ~5MSPS? How many devices do you need for that project evaluation phase? Also how many devices would you need this year?

    Yes, we have almost resolved the issue. I will email a link to you to order the parts early tomorrow.

    Best regards,

    Samiha

  • 0 in reply to l cj
    TI__Expert 8936 points

    Hi CJ,

    One more question, out of curiosity, which NI sbRIO board are you trying to emulate using your ARM + FPGA + ADC combination?

    Best,
    Samiha

  • 0 in reply to Samiha Sharif
    Prodigy 10 points

    we used several sbRIO boards and cRIO devices such as sbRIO-9626/27, cRIO-9035/38/45; 

    The disadvantage of sbRIO is that the AI channels are all scanning type with low sampling rate, while the cRIO is too much expensive. The focus is on the architecture of both, which is ARM+FPGA+ADC