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Design >> Mixed-Signal Design >> ENOB - from SDR, SNDR, SFDR, ?
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Message started by repah on Apr 21^st, 2020, 3:22am

Title: ENOB - from SDR, SNDR, SFDR, ?
Post by repah on Apr 21^st, 2020, 3:22am

Hello,

ENOB of a DAC or ADC - is it from the SDR, SNDR, or SFDR ?

I see various textbooks and application notes reference ENOB from these various sources.

Which is correct ?

Title: Re: ENOB - from SDR, SNDR, SFDR, ?
Post by DanielLam on Apr 21^st, 2020, 1:33pm

SDR doesn't exist, I think you mean SNR.

ENOB usually comes from SNDR. If there is no distortion, then SNR = SNDR because the distortion terms are negligible.

For a sine wave, enob = (sndr - 1.76)/6.02

If a different waveform is used (eg triangle waveform), the equation is sightly different.