[Tex/LaTex] How to label inputs to a logic gate using Circuitikz

circuitikztikz-pgf

Is there any way, or how would I go about adding labels and straight line inputs to logic circuit diagram? The code I have now is as follows:

\documentclass[11pt]{article}

\usepackage{circuitikz}

\begin{document}

\begin{circuitikz} \draw
(0,1) node[or port] (myor1) {}
(2,0) node[and port] (myand1) {}

(myor1.out) -- (myand1.in 1);

\end{circuitikz}

\end{document}

What I would like to do, more specifically, is label the inputs A and B leading to the first OR gate with whole words, or preferably phrases. I'd also like to be able to have a straight line leading to the second input of the AND gate, which is also to be labelled.

How can I go about doing this?

Many thanks!

Best Answer

You can place nodes for the labels:

enter image description here

To extend a line you can use

\draw (myand1.in 2) to (myand1.in 2 -| myor1.in 2)

which draws a horizontal line from the myand1.in 2 node to a point vertically below the myor1.in 2 node.

Code:

\documentclass[11pt]{article}
\usepackage{circuitikz}

\begin{document}

\begin{circuitikz} \draw
(0,1) node[or port] (myor1) {}
    (myor1.in 1) node [anchor=east] {A}
    (myor1.in 2) node [anchor=east] {B}
(2,0) node[and port] (myand1) {}
    %(myand1.in 2) node [anchor=east] {C}
    (myand1.out) node [anchor=west] {X}
    (myor1.out) to (myand1.in 1);

\draw (myand1.in 2) to (myand1.in 2 -| myor1.in 2)
        node [anchor=east] {C};

\end{circuitikz}

\end{document}

Related Solutions

[Tex/LaTex] 3-input logic gate on circuitikz

\documentclass{minimal}
\usepackage{tikz}
\usetikzlibrary{circuits.logic.US,circuits.logic.IEC}
\begin{document}
    \begin{tikzpicture}[minimum height=0.75cm] 
        \node[or gate US, draw,logic gate inputs=nnn] (A) {}; 
        \foreach \a in {1,...,3}
            \draw (A.input \a -| -1,0) -- (A.input \a); 
        \draw (A.output) -- ([xshift=0.5cm]A.output);
    \end{tikzpicture}

    \begin{tikzpicture}[minimum height=0.75cm] 
        \node[and gate US, draw,logic gate inputs=nnn] (A) {}; 
        \foreach \a in {1,...,3}
            \draw (A.input \a -| -1,0) -- (A.input \a); 
        \draw (A.output) -- ([xshift=0.5cm]A.output);
    \end{tikzpicture}   

\end{document}

enter image description here

By slight modification of this code you can acheive gates with more inputs (modifying inputs=nnn and \foreach \a in {1,...,3}).

For more, check TikZ & PGF manual section 29.3 Page 300

[Tex/LaTex] Drawing rectilinear curves in Tikz, aka an Etch-a-Sketch drawing

\draw (20,12) -- ++(2,0) -- ++(0,2) -- ++(-3,0) -- ++(45:3);

Use ++ before each new incremental coordinate to make it relative to the last one and put the pencil there.

Here's a complete example:

\documentclass{article}
\usepackage{tikz}
\begin{document}
\tikz\draw (20,12) -- ++(2,0) -- ++(0,2) -- ++(-3,0) -- ++(30:3) {[rounded corners=10pt]-- ++(5,0) -- ++(0,-6)} -- ++(-7,0) -- cycle;
\end{document}

Of course, combining this with the -| or |- path operators can simplify the code even further; the following two pieces of code produce the same result:

\tikz\draw (20,12) -- ++(2,0) -- ++(0,2) -- ++(3,0) -- ++(0,1) -- ++(1,0) -- ++(0,-3) -- ++(2,0);\par\bigskip

and

\tikz\draw (20,12) -| ++(2,2) -| ++(3,1) -- ++(1,0) |- ++(2,-3);

I don't think that defining commands in this case adds anything; in fact, I think it reduces the functionality of the existing syntax (which is already simple). The example demonstrates that you can use, for example, polar coordinates and modify (up to TikZ limitations) the path attributes midways; even if the current question doesn't require this, it's a good thing to have the possibility to do those kind of modification if they are required.

Best Answer

Code:

Related Solutions

[Tex/LaTex] 3-input logic gate on circuitikz

[Tex/LaTex] Drawing rectilinear curves in Tikz, aka an Etch-a-Sketch drawing

Related Question