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发表于 2012-5-18 10:36:04
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BSIM3v3.2.2 关于nqsMod的解释
The channel of a MOSFET is analogous to a bias dependent RC distributed
transmission line (Figure 5-la). In the Quasi-Static (QS) approach, the gate
capacitor node is lumped with both the external source and drain nodes (Figure 5-
lb). This ignores the finite time for the channel charge to build-up. One Non-
Quasi-Static (NQS) solution is to represent the channel as n transistors in series
(Figure 5-lc). This model, although accurate, comes at the expense of simulation
time. The NQS model in BSIM3v3.2.2 was based on the circuit of Figure 5-ld.
This Elmore equivalent circuit models channel charge build-up accurately because
it retains the lowest frequency poleof the original RC network (Figure 5-la). The
NQS model has two parameters as follows. The model flag, nqsMod, is now only
an element (instance) parameter, no longer a model parameter. To turn on the NQS
model, set nqsMod=l in the instance statement. nqsMod defaults to zero with this
model off.
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