From ef262312b91d2f7e10b83b56520e59de798d0059 Mon Sep 17 00:00:00 2001 From: Thomas Dehaeze Date: Tue, 16 Jul 2024 08:58:32 +0200 Subject: [PATCH] Update Content - 2024-07-16 --- .../zettels/analog_to_digital_converters.md | 30 +++++++++++++++---- 1 file changed, 25 insertions(+), 5 deletions(-) diff --git a/content/zettels/analog_to_digital_converters.md b/content/zettels/analog_to_digital_converters.md index d4ace06..889d576 100644 --- a/content/zettels/analog_to_digital_converters.md +++ b/content/zettels/analog_to_digital_converters.md @@ -14,7 +14,7 @@ Tags -- Delta Sigma +- Delta Sigma (Baker 2011) - Successive Approximation @@ -84,7 +84,7 @@ The quantization is: {{< youtube b9lxtOJj3yU >}} -Also see . +Also see (Kester 2005). ## Link between required dynamic range and effective number of bits {#link-between-required-dynamic-range-and-effective-number-of-bits} @@ -96,12 +96,27 @@ Also see . ## Oversampling {#oversampling} - +(Lab 2013) + +To have additional \\(w\\) bits of resolution, the oversampling frequency \\(f\_{os}\\) should be: + +\begin{equation} +f\_{os} = 4^w \cdot f\_s +\end{equation} + + +### When Oversampling and Averaging Will Work {#when-oversampling-and-averaging-will-work} + +> Key points to consider are: +> +> - The noise must approximate **white noise** with uniform power spectral density over the frequency band of interest. +> - The **noise amplitude must be sufficient** to cause the input signal to change randomly from sample to sample by amounts comparable to at least the distance between two adjacent codes (i.e., 1 LSB). +> - The input signal can be represented as a random variable that has equal probability of existing at any value between two adjacent ADC codes. ## Sigma Delta ADC {#sigma-delta-adc} -From <&schmidt20_desig_high_perfor_mechat_third_revis_edition>: +From (Schmidt, Schitter, and Rankers 2020): > The low cost and excellent linearity properties of the Sigma-Delta ADC have replaced other ADC types in many measurement and registration systems, especially where storage of data is more important than real-time measurement. > This has typically been the case in audio recording and reproduction. @@ -125,4 +140,9 @@ Therefore, even though there are sigma-delta ADC with high precision and samplin ## Bibliography {#bibliography} -<./biblio/references.bib> +
+
Baker, Bonnie. 2011. “How Delta-Sigma Adcs Work, Part.” Analog Applications 7.
+
Kester, Walt. 2005. “Taking the Mystery out of the Infamous Formula, $snr = 6.02 N + 1.76 Db$, and Why You Should Care.”
+
Lab, Silicon. 2013. “Improving the ADC Resolution by Oversampling and Averaging.” Silicon Laboratories.
+
Schmidt, R Munnig, Georg Schitter, and Adrian Rankers. 2020. The Design of High Performance Mechatronics - Third Revised Edition. Ios Press.
+