I'm facing some issues with the EVAL-AD7745/46EBZ capacitance to digital converter.
I'm using the I2C interface of the AD7745/46 to write and read its registers.
First I tried to set up the on-board "capacitance sensor length demo" and it works perfectly fine with my code.
However I don't get any meaningful values if I connect an external capacitance to the SMB connectors.
Of course I changed the register values so that the AD7746 should measure an external capacitance but it doesn't.
I always get a value close to zero even though I tried to connect capacitors ranging from 1pF to 4pF.
Of course I can explain the problem more detailed if there's somebody willing to help.