Jim Thompson wrote:
For sometime now I have been trying to build a behavioral model of
logic gates that was consistent with real-world behavior when mixed
into an Analog environment.

(Existing logic models, such as those in PSpice and LTspice are state
machines and do not behave properly when used for Analog applications,
such as when you build a crystal oscillator around a 74HCU04.)

So I now invite you to visit the Device Models & Subcircuits page of
my website...

http://www.analog-innovations.com/

and take a look at FauxMOSFET.pdf, where I have finally created a
purely mathematical behavioral model of a MOSFET... using, of course,
my favorite math function TANH :-)

With all derivatives continuous, it is suitable for modeling logic
elements that can be run in an Analog simulator environment.

Watch this space for further announcements as I develop inverters,
gates and complex functions that will run on any old analog simulator.

At first I was all "Hyperbolic tangent, WTF does that have to do with
SPICE?" Then I saw a TANH plot and the light came on. FWIW this guy
has an intro to Analog Behavioral Modeling.

http://www.ecircuitcenter.com/Circuits/ABM1/ABM1.htm

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\__/ Don Kuenz
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