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1.8V accumulation-mode MOS varactors
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Spice Model Information
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- Cell Name: :cell: `capbn_b`
- Model Name: :model: `sky130_fd_pr__cap_var_lvt` , :model: `sky130_fd_pr__cap_var_hvt`
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- Model Type: subcircuit
Operating Voltages where SPICE models are valid
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- :math: `|V_0 – V_1| = 0` to 2.0V
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Details
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The following devices are available; they are subcircuits with the N-well to P-substrate diodes built into the model:
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- :model: `sky130_fd_pr__cap_var_lvt` - low VT PMOS device option
- :model: `sky130_fd_pr__cap_var_hvt` - high VT PMOS device option
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The varactors are used as tunable capacitors, major e-test parameters are listed below. Further details on the device models and their usage are in the SKY130 process Family Spice Models (002-21997), which can be obtained from SkyWater upon request.
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.. include :: cap_var-table0.rst
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There is no equivalent varactor for 5V operation. The NHV or PHV devices should be connected as capacitors for use at 5V.
The symbols for the varactors are shown below:
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|symbol-cap_var-a| |symbol-cap_var-b|
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The cross-section of the varactor is shown below:
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|cross-section-cap_var|
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.. |symbol-cap_var-a| image :: symbol-cap_var-a.svg
.. |symbol-cap_var-b| image :: symbol-cap_var-b.svg
.. |cross-section-cap_var| image :: cross-section-cap_var.svg
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