Multiple device failures

[Makin-Things]

Firstly, we have tried contacting Melexis support directly (via both the support form on the website and direct phone call), but have had no response from anyone, which is extremely disappointing and unprofessional.

Now the issue. We have had multiple MLX90640's fail after a period of time (talking in the range of 20-30 out of about 100). We are using them connect to an STM32 and have ported the Melexis supplied drivers to the platform. Initially everything works fine, but after a period of time the sensors stop returning sensible images. Power cycling the board does not resolve the issue, they just keep returning garbage data.

The images always looks similar to this, with the sensor just pointing at the ceiling in the office.

There is some minor variation in the pixel values, but there are always the same warmer spots in the corners.

All I2C transactions are succeeding with no errors and the EEPROM seems to look normal (comparing it to other dumps that have been posted on this forum). We are running the sensors at 32Hz with Fast Mode Plus, but slowing it to 4Hz and Fast mode results in the same bad images.

I have attached a zip file with the ee_data, frame_data and aux_data.

I suspect the sensor is returning junk frame data. I would like to know what is going wrong with the devices, how to stop it happening and how to recover what appears to be a bricked device.

mlx90640_data.zip

I would like a response directly from anyone at Melexis so that we can discuss the issue and get it resolved. We are located in Canberra, Australia.

Regards
Simon Ratcliffe
Skykraft Pty Ltd

[LBuydens]

Hi Simon,

It seems 1 EEPROM cell in the sensor has been changed.

Can you please contact me directly at [email protected] to discuss further.
Right now we can't find your support request back in our system.

Regards,
Luc Buydens