INA300EVM: INA300

Hello, 

I will take a look into this and provide you with an update tomorrow. 

Thank you for your patience, 

Joe

 Hello, 

Thank you for your patience on this.

The way to test this is to set an RLIMIT value and run an input current through your shunt that passes your limit value. You will need to verify baseline offset and be able to measure single digit µV range based on when the Alert output trips. 

Take this first baseline measurement with the supply voltage for the INA310 constant and the supply voltage for the system constant (top node of shunt voltage). 

For PSR, change the INA310 supply voltage and record the change in the offset voltage in µV based on when the Alert output trips. 

For CMR, change the power supply voltage for the shunt and record the change in offset in µV based on when the Alert output trips. 

This is very difficult to measure but doing the above will allow you to calculate PSR and CMR. 

I hope this helps, 

Joe

Hi Joe Sir,

I really appreciate your kindly reply,

I measure the CMR as follows, could you help me to check,

step 1. Set VS=3.3V, VBUS (VIN+) 1V and measure the Alert output trip voltage( Alert pin pull low)

step 2. Change VBUS from 1V to 36V( max of VBUS), and record the Alert output trip voltage

step 3. Get the max and min of trip voltage from VBUS 1V to 36V

step 4. Calculate CMR by 20*log((max trip-min trip)/ 36V-1V) 

for the PSR, in my understand, test method is similar, the only difference is change VS from 2.7V to 5.5V, and VBUS=12V, then measure Vtrip.

and the formula could be ((max trip-min trip)/ 5.5V-2.7V) 

Is my above understanding right?

Hello, 

Thank you for your post. 

Let me look through your data and approach and get back to you tomorrow. 

Best Regards, 

Joe