I'm wanting a to increase the input impedance to a differential ADC. The ADC spec states that it can't handle a negative voltage lower than -100mV the ADC's supply can handle ~5V (this is a ATtiny1617)
I assume this means that the differential input works as follows into the IN+ and IN- pins of the ADC? IN+ = 0v & IN- = 0-5v, this would be the negative range of the ADC IN+ = 0-5v & IN- = 0v, this would be the positive range of the ADC
Assuming the above is correct. I need to buffer the input to increase the input impedance.
I've simulated the following circuit and it works fine, however I don't want R2 & R3 on the input as this reduced the input impedance, but if I remove these the simulation doesn't work.
The simulation also shows that X1-out & X2-inn swing negative. How should this be resolved?
Below with R2 & R3 removed