According to my understanding, it is impossible to get such resolution using "CapSense_GetSensorCp()".
Thanks for your reply. I understand that It is impossible to get capacitance ni
higher resolution with "CapSense_GetSensorCp()" API.
I got an advice from another expert to see "CY8CKIT-022 CapSenseR Liquid Level Sensing Shield."
I looked into the project and I found that they saved raw count value in case of no water into EEPROM
and they restored the value from EEPROM as an initial offset and subtract it from the raw count
value for the next time.
I will try this method.
If you only want to do the water detection, you can refer the CY8CKIT-022 :
But you may take "temp, different kind of liquid" into consideration.