How to choose FFT depth for ADC performance analysis (SINAD, ENOB)

1. How is ENOB calculated in ADC?
2. How is sinad of ADC calculated?
3. What is sinad in ADC?
4. What is the difference between sinad and SNR?

How is ENOB calculated in ADC?

ENOB is based on the equation for an ideal ADC's SNR: SNR = 6.02 × N + 1.76 dB, where N is the ADC's resolution. A real world ADC never achieves this SNR due to its own noise and errors. You can rearrange the equation to calculate an ADC's effective N, or ENOB as we commonly call it: ENOB = (SNR – 1.76)/6.02 dB.

How is sinad of ADC calculated?

The SINAD is found by computing the ratio of the RMS level of the input signal to the RMS value of the root-sum-square of all noise and distortion components in the FFT analysis, excluding the DC components.

What is sinad in ADC?

Six popular specifications for quantifying ADC dynamic performance are: • SINAD (signal-to-noise-and-distortion ratio), • ENOB (effective number of bits), • SNR (signal-to-noise ratio), • THD (total harmonic distortion), • THD + N (total harmonic distortion plus noise), • SFDR (spurious free dynamic range).

What is the difference between sinad and SNR?

Signal-to-noise ratio (SNR, or sometimes called SNR-without-harmonics) is calculated from the FFT data the same as SINAD, except that the signal harmonics are excluded from the calculation, leaving only the noise terms.