IV data extrapolation

All,

 I need some clarifications on the following questions

 1.When simulating the IV data for the Pull-up and Pull-down devices
   from -VCC to 2*VCC why is that extrapolation is done from
   -VCC to 0 for the Pull-up data when actually the dc source at
   the output pin is varied from -VCC to 2*VCC and similarly for
   the Pull-down devices the extapolation is done from VCC to 2*VCC.
   Is the data we obtain through simulation in these ranges not
   accurate?

 2.Can anyone tell me how this behavioral model for the buffers was
   actually arrived at?Can you please explain each block in detail?
   Does it in anyway represent an inverter circuit?

  Cheers and Best Regards,

    Geetha Rangarajan

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Received on Tue Nov 14 20:12:28 1995