I'd like to use atmega328p to read force with strain gauge. I'm using one 1k strain gauge and 3x 1k ohms dummy resistors.
I'm using DAC to remove offset from bridge.
As a result I'm getting so much noise on atmega pin.
I've tried changing R4 to 2,4k, 3k and 10k ohms. 2,4k and 3k helped just a little bit, but while using 10k output of ad8237 goes to 0 in a few seconds. I've removed C11 - nothing better happened.
AVCC is 3.3V with 10uH inducto in series. It's used to power strain geuge bridge, AD8237, DAC, atmega328p analog VCC.
Atmega328p AVCC and AREF are decoupled with 0.1uF capacitors.
Aver unues atmega pin is set as LOW output.
Is there any way I could remove that noise?
Everything solved by removing C23, thank You @EinarA
Now different problem is noise when touching sensor body. On the photo: lower amplitude - sensor lying on its own, higher amplitude - im touching sensor body with one finger. That's not big difference but it is. Sensor body is made od 1.4301 steel. Sensor body is not grounded. Is it a good idea to connect cable shield to body or just ground body? Cable shield is connected to ground on just pcb side.