INA226: ALERT output does not respond

Hello Wolfgang,

I have two questions.

1)What is the value of the configuration register 00h = 

2)What is the value you read when you read the Shunt Voltage Register 01h=

The reason I ask is to make sure the configuration is correct and is continuous or if you trigger a measurement.  The other reason is to verify that the register does measure above the limit.  I see you have it in transparent mode so is the alarm condition also continuous?

Hello Javier,

thanks for your fast answer!

Here my answer to this:

1)  Value of the Config-Reg 00h = 4127h

2) Values of the Shunt Voltage Reg 01h are between 23FFh and 243Fh (so the current is above the limit of 2328h)

And yes the alarm condition is in continuous mode. Is this the problem?

Regards

Wolfgang

Hello Wolfgang,

Do you have a pull up on the Alert pin?  Are you expecting and active Low?  I do not see an issue with your setup at all.  

You should see a high when not alarmed and low when alarmed. 

I will attempt to replicate to see if I have any issues.

Hello Javier,

okay.

But I forgot to mention that I can measure an output signal, but unfortunately not at the limit in the alert limit register.
I get a signal when I set the limit to a much smaller value, e.g. 1328h.

Regards

Wolfgang

Wolfgang,

I tried this and I got as expected.  I used the INA226EVM with the software provided and I placed a voltage on on the VIN+ and VIN- pins to create the differential voltage of the shunt inputs.  Below are no alarm condition and alarm condition.  The GUI displays the Alert signal which is also on the INA226EVM with an LED that was also lit up. Also displayed are the registers read.

Does the register 06h change as expected?  Could there be an issue with the output drive of the Alert pin for this device you have.  Could it have been damaged?

NO Alarm Condition

Alarm Condition: