Probably because LDO's are simple...usually.  And
cheaper quite often.  But as pointed out, very
inefficient.  I use LDO's when its 3.3-->2.5 and low
currents.  Anything higher current I use a
switcher..either off the shelf or drop it down on the
board.

On the Fairchild part...I'll ping my factory guy and
see if he has any comments.  I've never run into any
linear regulator (I assume that the OP knows what an
LDO is..) that doesnt require at least a cap on the
back side, and generally one on the input.

--- Olin Lathrop <olin_piclist@embedinc.com> wrote:
> > - Read the spec sheet and do whatever it says you
> need to do.
> 
> That's always essential, but I'm surprised nobody
> has stepped back and asked
> a broader question.  Why is this guy using an LDO
> when he wants 3.3V out
> from at least 8V in?  At the nominal 9V in he will
> spend 63% of the power
> heating the regulator.  This will likely be the
> limiting factor on the
> current capacity, not the maximum current specified
> in the data sheet.  He
> also said that this will usually be run from a 9V
> battery, and therefore
> total power consumption is probably important.  All
> this points to the wrong
> choice of regulator in the first place.
> 
> My first reaction given only this information would
> be to use a switcher.
> 
> 
>
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