Switching Regulators - How?

[Dave the Embalmer]

I'm sure many of you are familiar with the step-up/step-down switching regulators available from a variety of distributors. Many have very high efficiency, going up to the high 90s in percent. They are all inductor based regulators, and I have one simple question:

How do they work?

Its clear they don't invert into AC and use some micro transformer to step it up or down, so how do they do it? Any equations behind this? All I know is it involves an inductor in some way, but I see no way to get 5V from 1V using nothing but a transistor and a inductor...

 

[isaacj]

Here's a general explanation of how the various types of switchers work. **broken link removed**