LSM6DSOX Whoami signature

[andrea.lombardo]

We got from two different suppliers some LSM6DSOXTR and we expect to get 0x6C as fixed value in register 0x0F. ON the contrary we got 0x68 that looks to be the ID code of the oldest and obsolete LSM6D0. Is that possible? Is possible that I got wrong chips from the distributors? Is 0x68 actually the ID of the oldest LSM6DS0? Thanks!

[Kamil Duljas]

Hi, @andrea.lombardo​ I found similar topic. I hope it will help you:

https://community.st.com/s/question/0D53W00000LBjhlSAD/lsm6dso-issues-with-spi

[andrea.lombardo]

Hi Kemil, thank you for your feedback. Actually, I had found the link you sent me before posting my question. It was my understanding that the problem in the cases documented in the post was releted to difference between supply power and VDDIO power. In our circuit we use 3.3V for microcontroller, MEMS power and I2C lines and that should not be an issue.
Also the waveform of the signals of the I2C communication looks solid (see attached).

We are really out of options. Let me know if you have any other idea.

[Federica Bossi]

Hi @andrea.lombardo​ ,

I confirm you that 0x68 is the ID of LSM6DS0.

It's very strange, did you buy it from our website? Are you using our STEVAL adapter?

[andrea.lombardo]

I Federica, thank you for your feedback. We solved the problem. On the same I2C bus we also have a IIS3DWBTR and we discovered that it has the same address on the bus. So the 0x68 reply was actually the "merged" reply of the two devices. We fixed the problem changing the address of the IIS3DWBTR using the SA0 pin. By the way, let me inform you that on the IIS3DWBTR datasheet it is not mentioned its I2C addredd.