On 10/24/07, Harold Hallikainen <harold@hallikainen.org> wrote:
> I remember an application note from long ago (National, I think) where
> they made a switching regulator out of a linear regulator. If you take a
> regulator that has a sense input that has a ground referenced sense input
> (not something like the LM317 where the output is always 1.2V above the
> sense input), then put an inductor between the output and the filter
> capacitor, and connect the sense to the top of the filter capacitor, and
> add a catch diode between the regulator output and ground, you have a
> switching regulator. When the sense voltage is low, the chip output swings
> to the incoming rail. When it's high, it swings to ground.
>
> Anyway, that's what I remember from maybe 30 years ago...
>

You can use the LM317 as the PWM controller for
bulk converter. I have seen this in the previous job.

Xiaofan
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