JAJSE67C December 2017 – June 2022 AMC1311
Figure 9-3 shows an example of a TLV900x-based signal conversion and filter circuit for systems using single-ended input ADCs to convert the analog output voltage into digital. With R1 = R2 = R3 = R4, the output voltage equals (VOUTP – VOUTN) + VREF. Tailor the bandwidth of this filter stage to the bandwidth requirement of the system and use NP0-type capacitors for best performance. For most applications, R1 = R2 = R3 = R4 = 3.3 kΩ and C1 = C2 = 330 pF yields good performance.
For more information on the general procedure to design the filtering and driving stages of SAR ADCs, see the 18-Bit, 1MSPS Data Acquisition Block (DAQ) Optimized for Lowest Distortion and Noise and 18-Bit Data Acquisition Block (DAQ) Optimized for Lowest Power reference guides, available for download at www.ti.com.