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I've been struggling to find an example of an ideal phase response for a single port SAW resonator. In particular, I'm looking for a graph similar to this one:

which shows the admittance/conductance and phase response of a BAW resonator, but for a SAW resonator. Can I expect the same type of response out of a SAW resonator as that shown in the graph above, or will it be different? Forgive me if this is a basic question, I have a textbook on SAW devices in front of me but can't for the life of me find anything about the phase response in it (or in my extensive Google searches for that matter). Any help would be greatly appreciated!

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It seems that single-port devices like quartz crystals, ceramic resonators (including ultrasonic devices), BAW & SAW resonators all have an equivalent circuit of the same type:

schematic

simulate this circuit – Schematic created using CircuitLab

Co dominates at low frequency. Cm resonates with Lm at the series-resonant frequency, where Rm dominates. In your BAW graph, series-resonant frequency is approx. 6.263 MHz.
Above series-resonant frequency, reactance is inductive for a small span. In your BAW graph, this inductive region spans from 6.263 - 6.272 MHz.
At a frequency slightly higher than series-resonance, Cm combines with Co to yield anti-resonance (sometimes called parallel resonance). In your BAW graph, this is around 6.272 MHz.
Above the anti-resonant frequency, reactance becomes capacitive, and Co dominates. So yes (to answer your question), a SAW likely has a similar progression as your BAW example.
Quartz crystals have numerous spurious resonances which are often not characterized - only one dominant resonance (shown by the equivalent circuit above) is spec'd. Harmonic resonances are often not spec'd either. Some high frequency crystals are made to select 3rd, 5th, or even 7th harmonic - only the most active is spec'd.
I'd expect that any piezo devices have similar spurious resonances. It is sometimes possible that spurs can dominate in some circuits, but this is quite uncommon.

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  • \$\begingroup\$ Thanks @glen_geek, this helps. To help any others looking at this question I also went back to fundamentals, remembering that purely capacitive reactance results in a voltage that lags current by \$\frac{\pi}{2}\$ while purely inductive reactance results in a voltage that leads current by \$\frac{\pi}{2}\$. This explains the relationship between the reactance in the graph shown above for the BAW resonator and the phase, and would similarly apply for a SAW resonator. \$\endgroup\$ Dec 9 '16 at 14:44

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