An analytic charge-conserving nonquasistatic (NQS) model has been derived for long-channel MOSFETs and implemented in SPICE3. It is based on an approximate solution to the current-continuity equation. Comparison has been made among this model, the numerical solution to the 1-D current-continuity equation, and the quasistatic (QS) SPICE models. The charge injection at the turnoff transient of a NMOS switch has been simulated using this model and conventional QS models, and it has been found that the QS models give inaccurate results even for the moderately short channel (3-μm) MOSFETs when the input voltage is changing at the moment of turnoff. A differential sample-hold circuit has also been simulated using this model, and the results are compared with those from QS models. The CPU time using this model is around 3 to 4 times longer than for the conventional QS SPICE models.
|Number of pages||4|
|Journal||Technical Digest - International Electron Devices Meeting|
|State||Published - 1 Dec 1988|
|Event||Technical Digest - International Electron Devices Meeting 1988 - San Francisco, CA, USA|
Duration: 11 Dec 1988 → 14 Dec 1988