I am using a CN0350 with a pz accelerometer to measure small vibrations. I added a 1k ohm resistor at R8 to increase the overall gain, which has brought it up to an acceptable level, but now it is picking up a lot of interference. I installed it in a shielded enclosure but am struggling to figure out how to properly ground the board and cable shield to the enclosure. I made a microdot to BNC cable out of low noise RG-174 (the accelerometer only uses 2 wires), so the cable shield is in contact with the enclosure. It is my understanding that the ground from the accelerometer needs to be connected to the NEG pin of the CN0350, but this also would connect it to the enclosure and subsequently the ground of the other electronics.
The NEG pin of the CN0350 is biased at 1.25V which is half of the ADC reference voltage. The board has a separate GND pin which you can connect to the shield and enclosure to ground it.