https://devzone.nordicsemi.com/f/nordic-q-a/98473/smbus-between-bq78350-r1a-and-nrf5340---communication-is-not-stableHello everybody, We have a battery management system here based on TI bq78350-R1A with SMBus (slave, PEC disabled). Logic I2C levels now = 2.5V . (we tried 3.3V but with same issues). Time to time we see using oscilloscope that bq78350-R1A sendsen-USTelligent Community 13Thu, 15 Jun 2023 09:20:33 GMThttps://devzone.nordicsemi.com/thread/431194?ContentTypeID=1Thu, 15 Jun 2023 09:20:33 GMT137ad170-7792-4731-bb38-c0d22fbe4515:3768559e-7902-4557-b07d-4f0271f2b7ecSimpleSoft<p>THank you, indeed. Problem was inside of TI chip, SMBus works fine.</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/419566?ContentTypeID=1Tue, 11 Apr 2023 08:26:21 GMT137ad170-7792-4731-bb38-c0d22fbe4515:562fd3b0-a791-471e-9da2-54a24e771b22Kenneth<p>Hello,</p> <p>My suggestion would be to look at the datasheet for the sensor in question to try to find if there for instance are timing specifications (e.g. between I2C transactions) that you are not following. I think you may contact the sensor manufacturer to get their comment on what may cause the sensor to NACK communication if the address is correct.</p> <p>Clock stretching is fully handled in hardware, and will work automatically.</p> <p>Kenneth</p><div style="clear:both;"></div>