• State TI Thinks Resolved
  • Locked Locked
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 46 subscribers
  • Views 670 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

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.

ADC for 4 to 20 mA /0 to 10V

Pritesh Metha
Prodigy 190 points
Other Parts Discussed in Thread: ADS8688, ADS8698, MUX36D08, ADS125H02, MUX507

Hi,

I need ADC for PLC input module to measure 0 to 10V and 4 to 20 mA. Minimum resolution should be 24bit and 8 channel.

We found ADS8688 but it is 16bit. Can you please suggest alternate to this with higher resolution. 

  • 0
    TI__Mastermind 42031 points

    Hi Pritesh,

    Does your PLC AI module require 24 bits of resolution, or maybe it is actually 16-bit and you want a 24-bit converter in case of any dynamic range loss? Most PLC AI modules I have seen are 12-bit or 16-bit and usually do not require a 24-bit ADC (though sometimes a 24-bit ADC is used of course, for loss of dynamic range). I say this because the ADS8688 has scalable input ranges for most common PLC input signals (+/10V, +/15V, 0-10V, 0-5V, etc.). You can also take a look at ADS8698, the 18-bit version of this device, which provides added resolution if you are still worried about losing dynamic range.

    Another option you can take a look at is ADS125H02. This is a 24-bit delta-sigma ADC that can accept up to +/-15.5V inputs on a +/-18V supply. This device has 1x differential input channel so you can hook up any size mux to the front end to expand to 8x channels. For example, you could use MUX36D08 for an 8-ch differential mux. You could also take a look at our MUX50x series, for example MUX507 (also 8-ch differential).

    Let me know if you have any questions about these solutions.

    -Bryan