Part Number: INA220
This enquiry is about INA220's failing at an alarming rate in the first few weeks of service.
I cannot change the forum.
1st Line support could not help. They asked a lot of questions and I provided all the answers and now they want me to start from scratch again. Luckily I saved some of the correspondence. Please refer to the attached and let me know if you have any further questions.
TI support Transcript.docx
I think you have a grounding issue. Due to improper ground connections of INA220, shunt and battery, voltage drops and inductive kickbacks will occur which force the inputs of INA220 to go well below -0.3V.
These modfications should fix your issue:
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In reply to kai klaas69:
This does sound like over/under voltage type of failure, most likely under voltage given the configuration. If this is the case, good grounding should help and will reduce parasitic impedance, as Kai suggested.
Besides, you may replace R47/48 with ferrite beads with larger DC resistance such as 50Ohm. This value is larger than normally recommended but it might be necessary to increase the robustness of the system. You might also add Schottky diodes as clamp, before R47/48 and after the shunt.
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