INA219: Obtained floating output.

Shreya Umarani

Part Number: INA219
Other Parts Discussed in Thread: INA237

Hello,

I obtained floating output valued 0.86V, when input(VDD_DRV8_5V) and output load(VDD_DRVPA8_5V) isolated. Provided 3.3V to Vs pin and pull up to the I2C lines.
But the same issue wasn't faced with INA237.

Please let me know the reason.

Thanks and Regards,

Shreya Umarani

11 months ago

0 Mohamed Hamida 11 months ago

TI__Expert 6602 points

Hi Shreya,

I am looking into this and will get back to you tomorrow.

0 Mohamed Hamida 11 months ago in reply to Mohamed Hamida

TI__Expert 6602 points

Hi Shreya,

Our devices are not designed for isolation, so isolating IN+ and IN- would cause unpredictable behavior. If you are interested in isolation, you can reference the following reference designs:

https://www.ti.com/tool/TIDA-01608 - Positive bus voltages
https://www.ti.com/tool/TIDA-00313 - Negative bus voltages

The bus must reference the same GND as the device, any other configuration would cease unpredictable behavior and be out of device spec.

Best,

Mohamed

0 Shreya Umarani 11 months ago

Prodigy 10 points

Hello Mohamed,

Actually, it's not the issue with isolation. Without providing any input to the IC, observed floating output (IN-) w.r.t the DGND as 0.86V.

Please let me know the reason.

Thanks and Regards,

Shreya Umarani

0 Mohamed Hamida 11 months ago in reply to Shreya Umarani

TI__Expert 6602 points

Hi Shreya,

Can you measure the differential of IN+ and IN- to verify there is so signal being pushed to the INA?

Best,

Mohamed

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INA219: Obtained floating output.