PSP 103.4 has had very few changes applied to make it Xyce-specific.

  - Module attributes have been added to make it plug in to Xyce as an
    "M" device.  Similarly, attributes have been added to JUNCAP200 so
    it plugs in as the level 200 diode.

  - The two TR parameters have been declared with units of "degC" instead of
    "C".  Xyce's ADMS compiler interprets "C" as "Coulomb."  This has no impact
    on the model except to make Xyce output correct units in its documentation
    tables.

  - Several parameters had descriptions that included "^" to indicate
    exponentiation.  Because Xyce copies these descriptions into a
    data structure that is used to emit LaTeX tables, these characters
    cause syntax errors in the generated LaTeX.  They have been changed
    to "**".

  - The instance parameter  "M" has been added as a synonym for "MULT."
    Unlike many commercial simulators, Xyce does not define a universal
    "M" multiplier for devices, each device must define its own.

  - PSP 103.4 has a rewritten noise model that attempts to use one fewer
    node for correlated noise than previous versions of PSP do.  This method
    does NOT work in Xyce/ADMS yet, and so the noise contributions have
    been rewritten in this version to reinstate the second noise node.
