Hi Everyone,
I'm working through the ti precision labs series in hopes to understand how to correctly work with SAR and delta-sigma ADC's.
I've hit a point now where I've modelled the adc's input stage. From the datasheet
I'll be using the equivalent circuit on the left.
Additionally, as I have seen online the worst case analysis is usually done with coupling the converter side to ground as shown here in my simulation:
I've now hit the point where I need to select the resistor, capacitor and amplifier driving the SAR ADC.
First regarding the Amplifier:
Can anyone explain mathematically how they calculate the required bandwidth of the amplifier in the TI calculator or point me to some literature that explains it?
I'm unable to find it anything on this...
Lastly, I understand that the resistor that is added after the amplifier is for stability and the capacitor is the said "charge bucket" but what is the reason for the "Ground Sense" resistor. It's my first time encountering it in this series.
Any help will really be appreciated!
