BME 680 sensitivity

[BRP]

In  BST-BME680-DS001 table 5 shows "sensitivity" data derived of the organics in nitrogen atmosphere. Are there also data available in air?

My own measurements show about 0,6 Ohm per ppmv of EtOH in air. (about 8000ppmv, 100ms@250°C and 100ms@150°C).

Acetone (about 7000ppmv in air)  does not show a response.

[Jet]

Hi Sir:

     Did you mean TABLE 5 is the following picture?

  According to the gas mixtures, we had a test using Breath VOC* and a lab test chamber.

 Could you tell us more information? I didn't get your points.

 More test data or documents will be shared under NDA, recommand to contact the local FAE to get them.

[BRP]

...yes, these are the data. I suppose that the voc´s have been diluted in N2 and not in air. Is this right? My point is that the sensitivity in air is lower than in N2 due to a higher extend of reoxidation of the sensor which leads to a higher resistance of the sensor in air than in N2.

[Jet]

Hi Sir:

    Your comprehension is right.

    IAQ is the relative value and show the current air quality worse or better than the previous time phase.

    Maybe due to a higher extend of reoxidation of the sensor which leads to a higher resistance of the sensor, but it don't affect the relative results that BESC algorithm output.

    Mixed gas is tested in the laboratory and a single gas is not verified.

[BRP]

... thanks for the reply. For the application of a sensor it would be very helpful to get some more data about the behaviour under certain conditions. From my point of view BME680 today is a black box sensor inside black box of code. Some data released like for the e.g. MQ-8 sensor would be very helpful to check in advance if BME680 would work in other applications than air quality (IAQ) alone.