BME688 Gas Resistance

[SimaoLeite]

Hi

I am working with the BME688 sensor and I recently noticed that if I set the sensor's heating temperature to 0 degrees, after a while the resistance reaches the fixed value of 102M ohm. Can anyone tell me if this resistance value corresponds to the sensor's rest resistance and if it's necessary to set the sensor to this resistance value every time I make gas readings? I am only using BME68x API

[BSTRobin]

Hi SimaoLeite,

The 102M ohm value is under the range of BME688 static resistance.
Different gases have different resistance values.

[SimaoLeite]

Hi BSTRobin,

First of all thanks for the answer to my previous question, but could you tell me the reason why the initial gas resistance is never the same when I take two normal air readings in a row. I am using the standard heater profile with a difference in the times of each heater step (1 second for each heater step). The following graphs show the two readings taken and as you can see, the initial value is never the same. The first figure was the first one to be executed. The second figure corresponds to the second experiment.

 

 

[BSTRobin]

Hi SimaoLeite,

Sorry for the delay reply.
Because of the individual differences of every sensor part, the initial gas resistance value will not be the same.