I wanted to create a block diagram like this using tikz:

![cktikz.png](/image?hash=818767943d3baaf93b6f0b77d4ccead310ed5437dd35b5336923736434c4adc6)

It is meant to show how two 4-input-1-output digital circuit blocks
can be combined to get a 5-input-1-output block.

I figured circuitikz would be a good way to do this.

So I tried this:

```latex
\documentclass{article}
\usepackage{circuitikz}
\usetikzlibrary{positioning}
\begin{document}
\begin{circuitikz}
  \ctikzset{multipoles/thickness=3}
  \ctikzset{multipoles/dipchip/width=2}

  \draw (0,0)
    node[dipchip,
         num pins=10,
         hide numbers,
         no topmark,
         external pins width=0
        ] (C) {LUT4};
  \node [right, font=\tiny] at (C.bpin 1) {IN1};
  \node [right, font=\tiny] at (C.bpin 2) {IN2};
  \node [right, font=\tiny] at (C.bpin 4) {IN3};
  \node [right, font=\tiny] at (C.bpin 5) {IN4};
  \node [left, font=\tiny] at (C.bpin 8) {OUT};
  \node [right of=(C.bpin 1), font=\tiny] {H};
\end{circuitikz}
\end{document}
```

Which got part of one of the three blocks:

![cktikz-out.png](/image?hash=bb65019a05ecbc3d9c20f594255dc48d52dbf8c0c3acfdb12532ec89c3186540)

How can we draw wires branching off using circuitikz?
With a black dot representing branching off points.

I tried looking up the circutikz manual, but since I haven't yet spent
a lot of time on it, I couldn't get it.

Or would plain tikz be better in this case?

Can we use positions like `C.bpin 1.north`?