Current sensor recommendation inquiry

MJ,

Some information that would be helpful in making a recommendation for you is:

what the input dynamic range is for your system,

what the maximum error that the system can tolerate is,

and what size shunt resistor is acceptable.

Based on the information you have given me I would recommend the INA241A5 with a 400mΩ shunt resistor; I chose this because the INA241 has enhanced PWM rejection (and protection) and I am assuming you will be measuring a digital motor drive signal. This chip has an analog output, so if you were hoping to digitize the signal you would need an ADC as well. If you would like to use the chip bidirectionally, I would recommend using a 200mΩ resistor instead and holding the Vref pin at 6V.

I used our error calculator, available here if you wish to use it, to plot the error for you:

Here is a plot of the error for a 400mΩ shunt:

And for a 200mΩ shunt:

Let me know whether this chip and resistor will meet your specifications, or if your specifications require a different device.

Levi DeVries