FDC2214: Measurement level consistency is poor

Would you please provide a schematic of your circuit and snapshots of the signals on the INxA and INxB pins?

Regards,
John

hi,Thank you for your reply!

Below is my circuit diagram.IN0A Connects a sensor.

Below is signal on the IN0A

Below is signal between the IN0A and IN0B

Thanks for sharing your schematic. It looks fine.

Please check your signal amplitudes.

In the top plot, the peak voltage seems to go beyond the 1.8V maximum recommended in the data sheet.
In the second plot, the peak-to-peak voltage implies a peak value that is less than the recommended 1.2V.

regards,
John

When using differential mode，When the sensor is connected to IN0A and IN0B, the signal is shown below:

So，When I enable single-ended mode, Are the signals on IN0A and IN0B correct?

Thank you for the additional images.
I will review them and provide an update.

Some more questions:

1. In the mean-time, would you please provide a layout and a diagram of your system that shows the positioning of the PCB & sense coil, and the object you want to detect?
2. Also, you mentioned the reported capacitance values at the same height are inconsistent.
   Can you provide some detailed data that shows what you are seeing in your system?
3. Are you using any shielding to protect against EMI?
   Some customers have reported EMI-related issues with these parts..
   Grounded shielding near the sensor can create parasitics that compromise the sensitivity.
   The alternative is active shielding, which is supported by the FDC1004, a capacitive sensor with built-in active shield drivers.
   If this part interests you, there is a comprehensive collection of collateral at the E2E FDC1004 Frequently Asked Questions page.
   
   

Regards,
John