# Electronic – Why are switchers more efficient than linear regulators

linear-regulatorswitching-regulator

It is well-know that switching regulators are more efficient then linear regulators. I also know that linear regulator have to dissipate the difference between the input voltage and output voltage times the current as heat.

But why does this not apply to switching regulators with the same conditions: same input voltage and output voltage and current?

I know switchers can get hot; I have one on a board that gets so hot you can barely touch it, but then again it's only 2 1/2 millimeters on each side and looks like an ant compared to a through-hole 7805 with its heat sink.

\$P_{lin} = I_{load}\times{}(V_{src}-V_{load})\$.
\$P_{sw}= \mathrm{DC}(I_{on})(0\ \mathrm{V}) + (1-\mathrm{DC})(0\ \mathrm{A})(V_{off})\$,