On Wed, Apr 03, 2002 at 03:00:56PM -0800, Barry Gershenfeld wrote:
> >I was thinking similarly about dropping the voltage a bit before letting
> >the regulator have it, but I thought of 2 regulators -- first drop to 9V
> >or 8V, then the 7805.
>
> Another regulator, a resistor, a light bulb...Just remember that
> it all goes to the same place--heat--so you still have the
> same problem of shedding it.

Yes. And no. The yes part is that heat is of course generated. The no part is
that you can easily use a part that is better suited to manage the heat
dissapation. For example a TO3 power resistor controlled by that 7805 or a
zener can handle the heat better than the 7805 itself. Check out the use of
a pass transistor in your linear regulator.

>
> This is why switchers are different.  They don't "burn" the extra.

Or rather only burn very little during the switching phase.

BAJ

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