Analog-to-digital converter circuits (ADC) are usually equipped with analog low-pass filters to pre-condition the signal prior to digitization. This prevents signals with frequencies greater than the sampling rate from being seen by the ADC, causing a detrimental effect called aliasing. These analog pre-filters are thus known as anti-aliasing filters.



Determine which of the following Sallen-Key active filters is of the correct type to be used as an anti-aliasing filter: