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I've tried to use the crystal symbol in my simulations with no luck. I can model a crystal with the standard Rm,Lm,Cm & Co 4 parameter circuit model and get things to behave properly, but not when I simply use the built in crystal icon. Any one else experienced issues with the built-in crystal model?

I now understand the crystal icon is symbolic only, not modeled. I am now successfully modeling crystals with the 4-parameter model, so no need for a reply.

I've noticed something similar. In my experience, the built-in crystal symbol seems more suited for basic frequency-domain approximations than accurately reproducing startup and resonance behavior. Whenever I need realistic oscillator performance, I end up replacing it with the equivalent motional model (Rm, Lm, Cm + Co), just as you described.

I'd also double-check whether the surrounding oscillator circuit (load capacitors, bias network, amplifier gain) is fully modeled, since crystal oscillators are notoriously sensitive to initial conditions in simulation. If you can share the schematic, it might be easier to pinpoint whether it's the model or the oscillator topology. Reference:

CircuitLab Simulation Troubleshooting: https://www.circuitlab.com/docs/simulation-troubleshooting/ snake game CircuitLab FAQ (simulation limitations and component models): https://www.circuitlab.com/docs/faq/

Thank you, oftdiscreet, for your reply to my earlier query. I have finally been able to crawl up the learning curve enough to get the 4-element crystal model to do what I expect. I now realize the crystal symbol in the component sidebar is just a graphical placeholder with no intrinsic model attached. The Bode-plot-based frequency domain analyses agree nicely with what theory would predict when using the 4-element model, so I'm 'off to the races' as they say. Thanks, again, for your thoughtful response. I truly am enjoying 'polishing up' some of my long forgotten analog design skills using CIrcuitLab.

CircuitLab's built-in crystal symbol frequently fails to simulate correctly because, in many versions, it functions mainly as a schematic-readability placeholder rather than a fully editable SPICE-level component — unlike a real quartz crystal, which electrically is the 4-element Butterworth-Van Dyke (BVD) equivalent circuit consisting of motional resistance (Rm), motional inductance (Lm), and motional capacitance (Cm) in series, paralleled with static/shunt capacitance (Co) https://thepackagingmasters.com/custom/coffee/coffee-cups-with-lids/, so if the icon doesn't expose editable Rm/Lm/Cm/Co parameters or ships with unrealistic defaults, you'll see no proper resonance peak or wrong behavior; the fix you're already using — manually building the Rm-Lm-Cm-Co network with values pulled from your crystal's datasheet (Rm typically 10–150 Ω, Lm in the mH range, Cm in fF, Co a few pF) — is the correct, industry-standard approach, and this is a widely reported limitation rather than something wrong with your circuit.