Hi Erisson, Now I understand some of why the noise is higher. You have a voltage divider on the reference and are using 2.5V instead of 5V. The load cell sensitivity is 2mV/V and with 5V excitation the output maximum will be 10mV. At this range I would suggest using gain of 128 instead of 64 as this will provide the best input referred noise. I would also suggest removing the voltage divider on the reference and use 5V directly. The end result will be the same as what you are doing currently with less noise and drift. The voltage divider will have drift issues and will add thermal noise. Also because you are limiting current to the reference there may also be issues with sampling as you have no capacitor at the reference inputs for a charge reservoir. So remove R1 and short (or 0 Ohm resistor R2). I would also short R3 or make closer to 1 to 2 Ohms. 100 Ohms will restrict the ADS1232 from needed current, especially on power-up. C12 and C14 should be 1/10 or less the value of C13. It is possible to see a filter imbalance on the common-mode filters creating a difference voltage so you want to make the differential filter to be dominant. With C13 at 100nF, keep C12 and C14 to 10nF or less. I would make these changes and check the noise again. If you apply a short to the analog inputs and mid-AVDD supply, you should see similar numbers as shown in the noise table of the datasheet. Once you have proven the circuit, then you can remove the short and apply the load cell. You should see similar noise numbers. If you do not then you are picking up external noise that needs to be eliminated. Make the changes I suggested and report back the conversion values you are seeing. Best regards, Bob B
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