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Design >> Analog Design >> DAC noise analysis?
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Message started by Jacki on Dec 11^th, 2019, 1:13am

Title: DAC noise analysis?
Post by Jacki on Dec 11^th, 2019, 1:13am

Hello,

When we do the noise shaping, we need a DAC in the feedback loop and add the output of the DAC to the input of the sigma-delta modulator. Most of the time, we focus on the quantization noise in the ADC, but I wonder how about the noise from the DAC since its noise will be added to the input directly. Is it the same as the quantization noise or some other noise also become important.
Thank you very much for your knowledge and sharing.

Title: Re: DAC noise analysis?
Post by Jacki on Dec 13^th, 2019, 2:41am

I think if there is no excess loop delay, and with an ideal DAC, the DAC will form the original analog signal, and its noise is mostly from DAC like the thermal noise. hence the nonlinearity and excess loop delay are more important for the DAC design.

Title: Re: DAC noise analysis?
Post by neoflash on Jan 6^th, 2020, 9:08am

For SDM, DAC noise analysis is well studied in text books from Temes. Just read it.