About adamalfath

I found other forum post https://community.bosch-sensortec.com/t5/MEMS-sensors-forum/BSEC-BME680-i2C-bus-failure/m-p/47540 mentioned that the I2C bus is "collapsed", similar with my issue. It mentioned that the sensor has experienced extreme moisture conditions and that's maybe a clear factor on why the sensor got broke, but mine never goes outside the controlled environment, the humidity is always within the recommended state. ... View more

Yes, I'm too sure this problem is not caused by the wrong design/schematic. It must be something to do with the part itself, whether it defected from the beginning or broken in handling/soldering. I'm also interested in this internal I/O diagram: Can it be caused by this busted ESD diode? Because that 0.7XX Volt on I2C bus is like the line is shorted and the value close to the diode forward voltage. Maybe Bosch technical team ever find a problem with similar behavior like this? My goal here is to understand how this sensor failed and learn to prevent it from happening again. ... View more

Here's my schematic & board layout                   and a couple of information that may be useful: All the power & ground via is connected to the respective inner plane. All the power rail is present as it should be. The MCU (I2C master) is powered with an always-on +3V3 rail while the sensor is powered with +3V3' rail (with an apostrophe) generated by the 2nd LDO which the EN pin is toggled by MCU GPIO. No transient observed during switching ON/OFF operation. I misplace one decoupling capacitor that should be on the VDD(IO) rail to the CSB pin, but that should not be a problem. There's 10k pull-up to +3V3' on SDA and SCL near the MCU. All the I2C communication is working normally when the BME680 is removed from the board. ... View more