A best match is obtained between Level 3 and EKV MOSFET circuit simulators, even though the model parameters are somewhat artificial. These three examples illustrate some possibilities. The Level 3 simulations are confirmed with LabVIEW, PSpice Schematics and LTspice. EKV is matched between LabVIEW and LTspice. All three are the result of curve fitting as discussed in Part I. The best fit is around 2.5 V, which is the drain voltage of variable vg plots that are used in curve fitting. The full range is that of the range of the power supply magnitude.
UCRIT = 2 meg VMAX = 40 k
UCRIT = 2 meg VMAX = 0
UCRIT = 10 meg VMAX = 0
The last example will be used here for some curve-fitting exercises, although the UCRIT value is large. A DCsweep is performed on the following circuit for the two simulators.
The Pars 3 ICON (left) performs a curve fit to EKV-generated plots to obtain Level 3 model parameters on each run.
The Write ICON sends a .txt file to be read for comparison.
This program receives Plot Data (such as above DCsweep) or that from three arrays (top) and is sent according to the file path and name.
Level 3 and EKV compared with .txt files that are read.
Array Subsets are included to, for example, eliminate a title line in the data.
DC Transfer
Basic Op Amp
DC Sweep – UCRIT = 5 meg – VMAX = 0
UCRIT = 2 meg
UCRIT = 2 meg – VMAXn = 50 k, VMAXp = 20 k
OC curve fit, NMOS
OC curve fit, PMOS
Sat region KAPPA curve fit, NMOS
VMAX = 0
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