AFE4900: The ECG signal acquisition. And GND seperation.

Dear manager.

Hi.

I am currently testing ECG signal measurement. The circuit was constructed using the AFE4900.

However, I designed analog GND and digital GND into one. TIDA-01580 used GND separation and bead, is there a significant difference in signal acquisition?

When the voltage is measured with an oscilloscope without touching a finger, the LA (Left Arm) side is about 900mV and the RA (Right Arm) side is about 600mV.

So, the initial value is measured as shown in the figure below.

It seems like this because there is a difference in the initial DC value.

I need to experiment more, but will it be solved by separating GND?

Thank you.

Regards.