Minimizing channel-to-channel parasitic capacitance reduces the crosstalk induced on the PCB. This lower capacitance can be achieved by increasing the spacing between the analog traces to the multiplexer input.
In Figure 108, each multiplexer input has an RC filter. Use C0G- or NPO-type capacitors in the RC filter to help reduce settling when switching between multiplexer channels. When not switching the multiplexer, as discussed in Figure 43 and Figure 44, the RC filter can be omitted.