INA260: Current detection accuracy

Hello,

1. This percentage is the max system current sense gain error under the conditions of -10A to 10A, between -40 degrees C and 125 degrees C, Vs = 3.3V and Vcm = 12V. 

To calculate the error of this device there are two ways to do this we can either add all errors to get the worst-case total error or do a root-sum-square (RSS) total error for a more realistic device error. 

For the RSS total error, we would square all the errors add them and take the square root of the value. 

The three errors you stated do not encapsulate all error in the device. Doing the total error calculation with just those values may get you an inaccurate error value. 

To better help you calculate the error we would need more information about the system like Vs, Vcm, Max and Min current expected and operating temperature. Having these values, we could more accurately calculate total error. 

We also have a great tool for the INA260 that will help you better understand total error of the device. When on the INA260 product page scroll down until you find this interactive tool (image below). It will require some expected values but you can see how changing certain values changes the total error. 

If you have any questions please reply

Regards,

Castrense

Thank you for your reply.
I checked "Current sense amplifier error analysis INA260" on TI WEB.
I have some questions.
(Question)
In the "Ideal shunt resistor" item, the RSS Error does not change even if the value is changed.
Is it because the INA260 has a built-in resistor?
If YES, is the resistance variation also calculated?
After that, is the variation of the built-in resistance 2mΩ 0.1%?

Best regards,