Hello all !
I use AD7766-2 converter in my project
I apply 5v at Vref+ input from ADR435, and use common mode voltage Vref/2=2.5v.
I checked that Vref/2 in +-5% range!!!
And I apply diff sin signal (peak to peak) 2.6v p-p around 2.5v (Vref/2) to inputs V+ and V-. Summary:(from 2.5v-1.3v to 2.5+1.3v)
And I see that ADC overflows !!!!,
If apply 2.4v p-p around 2.5, that ADC not overflows but samples from ADC near top level !!!
In datasheet page 20 say: "When the AD7766-2 Vref pin has a 5v supply, the common mode is at 2.5v, meaning that the maximum inputs that can be applied on the differential inputs are a 5v p-p input around 2.5 v."
Why ADC overflows if i apply only littlemore half range ?