MPX5100DP E-Tensiometer

[andikun]

Dear NXP's team
I'm currently working on making an e-tensiometer as one of the tools I use for my research.
I use the MPX5100DP as a sensor to measure the suction (negative pressure) of the tested sample.
In practice, I have tried to build the device with an Arduino microcontroller and found a problem regarding the minimum pressure that can be measured. I know that the differential sensor measures the difference between the large and small pressure to get the current pressure value, but after I tested the device, it can only issue a minimum suction of -2.06 kPa (A_DC real=22; A_DC corrected=21.92). Apart from that, I tried to suck it hard, but the result is still the same, at least A_DC = 22. On the other hand, positive pressure runs normally and doesn't get stuck as it does negative pressure.
Going from (A_DC=41) to (A_DC=22) is easy and fast, but reaching the value of 22 will not change more, even with powerful suction. From that chronology, I would like to ask:
1. Is the minimum DP of this sensor only up to analog 22? can this accuracy be improved in MPX5100DP?
2. If it can't be improved, do you suggest what sensors I can use for the e-tensiometer with the appropriate readings?
3. Is the sensor in the NXP?
Thank you for your attention.
Regards.

[andikun]

my mistake was not careful. I forgot that strain gauges can only measure compression or tension. suction works fine on the other side of the hole, problem solved. Thank you.