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I used an ACS 723 current sensor to measure a very small current. The output of the current sensor gets converted into a proportional voltage.

I have attached the output of the current sensor. Could somebody tell me the formula or a way to convert this voltage into current?

enter image description here

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  • \$\begingroup\$ The datasheet specifies something like 100~400mV/A, depends on your model. \$\endgroup\$
    – tlfong01
    Dec 30 '20 at 15:06
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    \$\begingroup\$ Thank you so much \$\endgroup\$ Dec 30 '20 at 15:35
  • \$\begingroup\$ You are welcome. Have a great new year. Cheers. \$\endgroup\$
    – tlfong01
    Dec 31 '20 at 1:43
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You start with the datasheet.

For each specific module, there is a table that gives you a "Zero Current Output Voltage," and a "Sensitivity."

enter image description here

Subtract the zero current voltage from your measured voltage then divide by the sensitivity to get current.

Assuming a Vcc of 5V and that you are are using the "xLLCTR-5AB" model (from the example table,) then your measured current (as shown in your example) would be around \$\frac{2.39V-2.5V} {400} = -0.275 amperes.\$


There are more items in the datasheet that will help you get better values (expected voltage offset errors, linearity errors, etc.) but the method above will give you a starting point.

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    \$\begingroup\$ Thank you so much for your help. I will follow this and learn more. \$\endgroup\$ Dec 30 '20 at 15:35

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