A first-order charge conserving MOS capacitance model

The Meyer capacitance model (see RCA Rev., vol.32, p.42-63, 1971) fails to obey the charge conservation law. It is shown that the charge nonconservation in the Meyer model is not due to any physical assumptions. Rather, it is caused by the mathematical error of characterizing a multidimensional function (the stored charge on the four terminals of a MOSFET) by an incomplete subset of its partial derivatives (the partial derivatives of the gate charge). This conclusion is supported by developing and implementing a correct mathematical characterization of the MOS charges based on the same physical assumptions used in the Meyer model. One important outcome of this exercise is that the nonreciprocal nature of MOS capacitive coupling is evident even in a first-order physical model of the device.<
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