INA181: INA181

Ok, Thanks for the reply. 

I wanted to know below also:

Max Current is - 10 A, Rsense used is 4 mOhm, 

So 1. at 10A-> INA181 will sense 40 mV 

2. at 1A-> INA181 will sense 1 mV. 

Is this range from 1 mV to 40 mV makes sense for INA181?? I am more worried about lower range i.e. < 1mV. 

Chetan,

Thanks for the question and using the E2E forum.

We are out of the office due to the U.S. holiday but will respond to your question when we return to the office Monday, 4/21.

Hello Chetan, 

I agree with you that the lower range will be limited by the input offset voltage of the device. At 500uV maximum input offset voltage, this will lead to roughly 12.5% error attributed to offset alone at 4mV sense voltages at your 1A condition.

Is there any way that you can increase the shunt resistor to 40mOhms?

Best Regards, 

Joe

YEs was thinking to increase to 6 mOhm. Is it OK then ??

6 mOhm means Now worst case error at 1A will be ~8.3 % i.e. current will read by ADC is ~ 0.9 A Right ??

Hello Chetan, 

Yes, you are correct. At 1A, the measurement by the ADC can be 1.083A or 0.916A. 

If this meets your error requirements at 8.3% error, then the 6mΩ resistor will work as your shunt. 

I hope this helps, 

Joe