SBAA591 December 2023 REF54
This application note describes low flicker noise (0.1 Hz to 10 Hz band) measurement methodology and test setup recommendations for precision series references. Low noise measurement requires ultra-low setup noise, which can be achieved by selecting low-noise BOM for the band pass filter and proper design or layout techniques. The lowest noise reference REF54250CDR (flicker noise = 275 nV pk-pk with 100 μF capacitor on NR pin) is used to illustrate the component selection and board design to measure the noise floor with < 1.5% error from the measurement setup.