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I am designing loadcell (spec) measuring using 24-bit adc (MCP3561) with excitation 10 V. But I couldn't find the reference design for 6-wire loadcell that its sense pins connect to ref+ pin of ADC. Most design usually use excitation 5 V.

What I am trying to accomplish here is to still use 10 V excitation and still compensate excitation voltage drop with both sense pins of loadcell.

If I use voltage divider for put down voltage to 1.2 V (according to the spec of MCP3561). I am not sure if this is going to work due to the resistance might change.

If there is a better solution, please let me know.

I have added the reference design that I find here

enter image description here

As you can see the sense+ and sense- pin is connected to excitation voltage and Ref pin of ADC.

So when the excit. voltage drop due to the loadcell your measurement value is compensated.

This is actually work when your excit. voltage is 5V or 3.3V. But mine is 10V. ADC ref pin can receive only AVDD max, which is 5V.

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    \$\begingroup\$ "6-wire load cell" is pretty useless information without datasheet. I've seen precision load cells with embedded eeprom using up 2 extra wires, as well as thermal sensors and something as simple as supply voltage feedback \$\endgroup\$
    – Maple
    Commented Feb 29, 2020 at 21:10
  • \$\begingroup\$ @Maple I have added loadcell spec for referenec thank you for pointing this out. I will learn more about supply voltage feedback \$\endgroup\$
    – LazyLabor
    Commented Feb 29, 2020 at 21:16
  • \$\begingroup\$ First point of contact for help should be the people who made it. They should know. You might let them know the "Connection scheme" section on their website seems to be empty, and ask them what should be in it. \$\endgroup\$
    – user16324
    Commented Feb 29, 2020 at 22:28
  • \$\begingroup\$ The page in your reference has empty "connection scheme" box. The downloadable user guide PDF shows standard 4 wire schematics. Even if they supply shielded cable not mentioned in the PDF it still comes down to 5 wires, not 6. \$\endgroup\$
    – Maple
    Commented Feb 29, 2020 at 23:23
  • \$\begingroup\$ @BrianDrummond Sorry for misunderstanding. What I really want is to measuring the common 6-wire loadcell with 2mV/V sensitivity. The loadcell I have mention in this topic is the one that I actually use for reference, which the actual one come with 6-wire plus shield wire. Here's the reference of 6-wire measurement design link. You can see that both sense pins is connected to Ref+ and Ref- of ADC. \$\endgroup\$
    – LazyLabor
    Commented Mar 1, 2020 at 3:28

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