• State Resolved
  • Locked Locked
  • Replies 4 replies
  • Answers 1 answer
  • Subscribers 48 subscribers
  • Views 611 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.

Original question:

ADS131E04: Diffirenences between E , A and M

ADS131E04: Differences between A, E, and M for 60Hz AC Power Measurements

Collin Wade
Prodigy 50 points

Part Number: ADS131E04

Hi,

I've looked through the datasheets for all three types, and am curious which ADC would work best for measuring AC Power (120-347VAC, voltage-divided down) at 60Hz. Having a PGA is not a big concern for me, as I will put all signal through a pre-amplifier.

Thanks for your help!

  • 0
    TI__Guru 69476 points

    Hi Collin,

    Welcome to our forum and thank you for your post.

    The initial reply in this post highlights some of the key performance differences. In addition, the interface and data rates may also determine the device you ultimately design with. Both the ADS131A0x and ADS131M0x families are used in power measurements today with a direct input from an AC voltage divider input, or a CT, Rogowski coil, or shunt current input.

    Regards,

  • 0 in reply to Ryan Andrews
    Prodigy 50 points

    This is perfect, thank you! Is the 'E' series just an older chip? It seems like this one could also be used for 60Hz AC Voltage Measurements. The difference in sample rates between the three, along with the interface, and PGA aren't very important in my application.

    Also: I noticed that these can operate in either single-ended or differential configurations. Is it possible to read "Vin, Negative" with respect to GND? I know the standard is to read "Vin, Positive"

  • 0 in reply to Collin Wade
    TI__Guru 69476 points

    Hi Collin,

    Yes, the E series was released first in 2012, but it is still an appropriate device for AC voltage measurements (see section 10.1.4 for Power Monitoring applications).

    I'm not sure what you mean here. The absolute input voltages must always remain within the analog supplies. The exception is for devices which feature a negative charge pump (A and M series). Either way, each ADC channel is always converting INxP - INxN, so you can just invert the polarity of the conversion result if desired. If you meant something else, please let me know

    Regards,

  • 0 in reply to Ryan Andrews
    Prodigy 50 points

    Hi Ryan,

    Sorry for the confusion, you've answered my question perfectly. I was interested to see if any of the ADS131 variants (E, M, or A) could read a voltage between one of the Vin Inputs and GND (ex: Vin_p = 3V, Vin_n =2V, reading '2V' or '3V' in addition to Vin_p - Vin_n = 1V). From what you're saying this is not possible, as all 3 always read the difference between Vin_p and Vin_n. I was just curious to see if any of these could work in both a single-ended and bipolar configuration.  

    Thanks for your help!