Hi,
In TI document SBAA256A Driving a SAR ADC directly without a front-end buffer circuit (low-power, low-sampling-speed DAQ), TI shows how to sensing a slow signal without opamp anti-aliasing filter. I also often see such circuits used in real applications, mostly in automotive applications. One basic question come to my mind about such kind of ADC interfacing circuit is what about the aliasing issue. The sampling frequency may be smaller than the RC filter cut off frequency. Could you give me some comments about my aliasing concerns?