JAJSLQ5C April 2021 – September 2022 ADS127L11
PRODUCTION DATA
Total harmonic distortion (THD) specifies the dynamic linearity of the ADC with an ac input signal. For the THD measurement, a –0.2-dBFS, 1-kHz differential input signal with VCM equal to the mid-supply voltage is applied. A sufficient number of data points are collected to yield an FFT result with frequency bin widths of 5 Hz or less. The 5-Hz bin width reduces the noise in the harmonic bins for consistent THD measurements. As shown in Equation 11, THD is calculated as the ratio of the root-sum-square amplitude of harmonics to the input signal amplitude.
where: