I am designing circuit for 16-channel universal non-isolated analog input . I am using differential multiplexer for channel selection and two more multiplexers to select signal processing block depending on input type(TC/RTD/4-20ma/0-10VDC). At input channel I m providing transient protection using TVS diodes and clamping diodes. Should I put common mode and differential filters at the input connectors after protection or should place a common filter for all channels after multiplexer (before instrumentation amplifiers or 24-bit sigma-delta ADC). Using a common filter may reduce channel to channel data acquisition speed, on the other hand placing it for each channel at the connectors just after protection hardware increases number of filters.Please suggest me where should I place filter?