There is no single "official" link from a monolithic vendor like Texas Instruments or NXP that provides a standalone file download link. Instead, manufacturers embed models within simulation tools or support pages. Below are the for the CD4051 SPICE model.

Once you have obtained the CD4051 SPICE model, you can use it in your SPICE simulator to analyze the behavior of the IC in various circuits. Here are the general steps:

https://www.ti.com/lit/zip/sccm073 (Note: Always verify in a browser)

Depending on your simulation environment, you can obtain the necessary .lib or .sub files from these reputable sources:

Texas Instruments manufactures the CD4051B (the 'B' is important—it's the improved version). TI is the most reliable source for SPICE models.

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