Circuitry for and methods of analyte measurement Circuitry for measuring a characteristic of an electrochemical cell, the circuitry comprising: a hysteretic comparator having a first comparator input, a second comparator input and a comparator output; a feedback path between the comparator output and the second comparator input configured to provide a feedback signal to the second comparator input; and a loop filter configured to apply filtering to the feedback path to generate the feedback signal, wherein the loop filter comprises the electrochemical cell.