> I selected the Abracon ABLS at exactly that speed (how convenient
8^D),
> and
> on its datasheet it specifies "Load Capacitance" at 18pF and Shunt
> capacitance at 7pF. My questions:
> 
> 1-Should I use 18pF capacitors for my circuit? (I think the real
question
> is
> what's the difference between load and shunt capacitance?)

Arrghh.. Pet peeve attack. :)

The caps are seen by the crystal as being in series, so start with a
value that is TWICE what is specified. In your case, 36pF. Now estimate
a value for stray capacitance on those leads in your circuit. A good
guess might be 5 pF or so. Subtract from the previous value, and round
to 30pF.  Start there.  Check a prototype, and see where the crystal is
oscillating. Trim the values to obtain dead-on frequency, and you're
there. 

Will it "work" with 18pF?  Probably. Most of the time, under good
conditions.


> 2-What's the recommended type of capacitor in this case (ceramic,
> tantalun,
> electrolytic, etc). Is SMD fine?

You want caps that are stable over temperature, and relatively tight
tolerance.  Tantalum or electrolytic aren't even available in such low
values.  SMD multilayer ceramics would be a workable choice.



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