Graphing / visualizing power tree?
Nearly a one word answer: Graphviz.

You just have to get the tree that you're trying to visualize into the DOT language.

VBAT going to PMIC, which goes to 3V3LDO, and 5VSMPS:

$ cat power.gv
digraph power {
   VBAT -&gt; PMIC
   PMIC -&gt; "3V3LDO"
   PMIC -&gt; "5VSMPS"
}
$ dot -Tpng power.gv -o power.png


power.png contents: