> All crystals have both series and paralell resonances.  They are only
> guaranteed to perform within spec on one or the other.
> If you put a series xtal in a paralell circuit it will probably run, but you
> will NEVER get it on the right frequency. The two points
> obviously can't be the same frequency.

Just to put it into perspective. The difference between parallel and
series resonant frequencies is in the order of  0.05%. eg. 5kHz on a
10MHz crystal. When a crystal is spec'd as series or parallel it
describes the measurement conditions, not how the crystal is
constructed. It's similar to having two thermisters, one spec'd at 20
degrees and another at 25 degrees.

Steve.
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Steve Baldwin                Electronic Product Design
TLA Microsystems Ltd         Microcontroller Specialists
PO Box 15-680, New Lynn      http://www.tla.co.nz
Auckland, New Zealand        ph  +64 9 820-2221
email: steveb@tla.co.nz      fax +64 9 820-1929
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