The CTSD16 module integrates a single sigma-delta ADC with ten external inputs and four internal inputs. The converter is designed with a fully differential analog input pair and a programmable gain amplifier input stage. The converter is based on second-order over-sampling sigma-delta modulators and digital decimation filters. The decimation filters are comb type filters with selectable oversampling ratios of up to 256.

The CTSD16 is proceeded by an analog multiplexer which is used for channel selection, followed by a unity gain buffer stage useful when sampling high impedance sensors.

The CTSD16 can use as its reference the internal bandgap voltage from the REF module or an external reference at the VeREF+ pin.