JAJSOX0B March 2024 – November 2024 ADS127L18
PRODMIX
Signal-to-noise ratio (SNR) is a measure of noise performance with a full-scale ac input signal. For the SNR measurement, a –0.2dBFS, 1kHz test signal is used with VCM equal to the mid-supply voltage. Equation 12 shows that SNR is the rms value ratio of the input signal to the root-sum-square of all other frequency components derived from the FFT result of the ADC output samples. DC and harmonics of the original signal are excluded from the SNR calculation. If an FFT window function is used because of non-coherent sampling, the spectral leakage bins surrounding the original signal are removed to calculate SNR.
where: