File:4-bit Successive Approximation DAC.gif

Original file(1,218 × 962 pixels, file size: 303 KB, MIME type: image/gif, looped, 60 frames, 1 min 0 s)

Summary

Description
English: The animation shows the bitwise approximation of an analog input value within a 4-bit ADC. The simulation is based on a reference voltage of 5V and several different input voltages in the range from 0V to 5V. The animation was created using TIKZ, beamer and XeLaTeX.
Date
Source Own work
 \begin{frame}{Successive Approximation -- example of a 4-bit ADC}
   \noindent\begin{tikzpicture}[x=0.05\textwidth,y=0.05\textwidth]
       \useasboundingbox (-6.5,-8.5) rectangle (13.5,6.5);
       \path(0,0) node[anchor=south west,inner sep=0pt](im){\includegraphics[width=.5\textwidth]{20191120_sar}};
       \path (0,5)node[anchor=east,blue]{$clk$};
       \path (-3,-7) coordinate(origo);
       \draw [black, very thick, -latex'] (origo) -- node[anchor=north]{\small\slshape\bfseries time} ++(10.5,0);
       \draw [black, very thick, -latex'] (origo) -- node[anchor=south,rotate=90]{\small\slshape\bfseries voltage} ++(0,6);

       %\grid{-10,-10}{14,10}
       %\draw[green] (-6.5,-8.5) rectangle (13.5,6.5);
       
       \path(7.5,-1)node[anchor=north west,inner sep=2pt,rounded corners=2mm,draw=black,fill=LemonChiffon1,text width=0.30\textwidth]{%
       \scriptsize         %
       \begin{tabular}{lr}
         \multicolumn{2}{c}{Resolution:}\\
         $\SI{5}{\volt}\times\sfrac{1}{2}$ & \SI{2.5000}{\volt}\\
         $\SI{5}{\volt}\times\sfrac{1}{4}$ & \SI{1.2500}{\volt}\\
         $\SI{5}{\volt}\times\sfrac{1}{8}$ & \SI{0.6250}{\volt}\\
         $\SI{5}{\volt}\times\sfrac{1}{16}$ & \SI{0.3125}{\volt}\\
         \dots & \\
         $\SI{5}{\volt}\times\sfrac{1}{1024}$ & \SI{0.0049}{\volt}\\
       \end{tabular}};

       \edef\vin{4.0}

       \foreach[count=\v,
         evaluate=\v as \startframe using int(1+6*(\v-1)),
         evaluate=\v as \lastframe using int(\startframe+5)]
         \vin in {0,0.5,1.0,1.3,2.0,2.6,3.0,4.0,4.5,5.0}%
       {
         \only<\startframe-\lastframe>{
           \path (0,1)node[anchor=east,Chartreuse4]{\scriptsize$V_{in}=\SI{\vin}{\volt}$};

           \draw [Chartreuse4,line width=0.3mm] ($(origo)+\vin*(0,1)$) -- ++(10,0)node[pos=-0.07,anchor=east]{\scriptsize$V_{in}=\SI{\vin}{\volt}$};
         }
         \foreach[%
            count=\i,%
            evaluate=\i as \frame using int(\startframe+\i),%
            remember=\val as \lastval (initially 0),%
            evaluate=\lastval as \vcmp using 5*(\lastval+\val)/16,%
            ]%
            \val in {8,4,2,1,0}
         {
           \pgfmathbin{16+\val+\lastval}
           \edef\bitstring{\pgfmathresult}
           \pgfmathsetmacro{\keep}{ifthenelse(\vin >= \vcmp,1,0)}

           \only<\frame-\lastframe>{%
               \draw [blue,line width=0.3mm] ($(origo)+\vcmp*(0,1)+{\i-1}*(2,0)$) -- ++(2,0)
                  node[pos=0.5,anchor=south,inner sep=2pt,fill=white,opacity=.7]{\tiny$\SI{\vcmp}{\volt}$}
                  node[pos=0.5,anchor=south,inner sep=2pt]{\tiny$\SI{\vcmp}{\volt}$}
                  node[pos=0.5,anchor=north,inner sep=2pt,fill=white,opacity=.7]{\tiny 0b\StrRight{\bitstring}{4}}
                  node[pos=0.5,anchor=north,inner sep=2pt]{\tiny 0b\StrRight{\bitstring}{4}};
           }
           \only<\lastframe>{%
               \ifthenelse{\equal{\val}{0}}%
               {
                 \path (im.south west) node[anchor=north west,inner sep=2pt,blue,rounded corners=1mm,fill=yellow!60]{\small result: 0b\StrRight{\bitstring}{4}\quad $V_{in} \approx \SI{\vcmp}{\volt}$};
               }%
           }
           \only<\frame>{%
             \foreach[count=\j,evaluate=\j as \x using 0.6*(\j-1)+1.5,evaluate=\j as \k using int(\j + 1)] \bit in {3,2,1,0}
             {
               \ifthenelse{\equal{\i}{\j}}%
               {
                 \path (\x,3.6) node[anchor=south,inner sep=0pt,red]{\StrChar{\bitstring}{\k}};
               }%
               {
                 \path (\x,3.6) node[anchor=south,inner sep=0pt,blue]{\StrChar{\bitstring}{\k}};
               }
             }
             \draw[blue,line width=.3mm] (5.5,2.3) -- (6,3.5)node[anchor=south west,inner sep=0pt,blue]{\scriptsize$V_{cmp}=\SI{\vcmp}{\volt}$};
             \ifthenelse{\equal{\val}{0}}%
             {}%
             {
               \ifthenelse{\equal{\keep}{1}}%
               {
                 \path (7.0,5.2)node[anchor=south,red]{\scriptsize$V_{in} >= V_{cmp}\,\,\Rightarrow\,\,$ keep bit};
               }
               {
                 \path (7.0,5.2)node[anchor=south,red]{\scriptsize$V_{in} < V_{cmp}\,\,\Rightarrow\,\,$ drop bit};
               }
             }
           }
           \pgfmathsetmacro{\val}{ifthenelse(\vin >= \vcmp,int(\lastval+\val),int(\lastval))}
         }
       }
     \end{tikzpicture}
 \end{frame}
Author Uwezi

Licensing

I, the copyright holder of this work, hereby publish it under the following license:
w:en:Creative Commons

attribution share alike

This file is licensed under the Creative Commons Attribution-Share Alike 4.0 International license.
You are free:
  • to share – to copy, distribute and transmit the work
  • to remix – to adapt the work
Under the following conditions:
  • attribution – You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use.
  • share alike – If you remix, transform, or build upon the material, you must distribute your contributions under the same or compatible license as the original.

Captions

Animation of a 4-bit Successive Approximation DAC.

Items portrayed in this file

depicts

File history

Click on a date/time to view the file as it appeared at that time.

Date/TimeThumbnailDimensionsUserComment
current16:05, 21 November 2019Thumbnail for version as of 16:05, 21 November 20191,218 × 962 (303 KB)UweziUser created page with UploadWizard
The following pages on the English Wikipedia use this file (pages on other projects are not listed):

Global file usage

The following other wikis use this file: