eldo_user

Statistical Experimental Design and Analysis
Example of Experiment Design
.PARAMDEX
+ DL NOISE/SIG=2.5
+ DW NOISE/SIG=2.5
+ TOX NOISE/SIG=2.5
+ VFB NOISE/SIG=2.5
Note that these statements are equivalent to the following:
.PARAMDEX
+ P(DL) NOISE/SIG=2.5
+ P(DW) NOISE/SIG=2.5
+ P(VFB) NOISE/SIG=2.5
+ P(TOX) NOISE/SIG=2.5
Specifying Model Parameter Selectors
The following example illustrates the use of the constructs M(.,.) and EM(.,.) with the inter and
intra variations. The use of M(.,) is not very useful in this case but we will assume that the
statistical variations were stated as follows:
.PARAM TOX=0.015
.MCMOD NCH TOX LOT/GAUSS=0.0003
.MCMOD PCH TOX LOT/GAUSS=0.0003
There are two independent random variables TOX associated with the PMOS and NMOS
transistor. Two PMOS, or respectively two NMOS, transistors are assumed to be perfectly
tracking each other, but the PMOS and NMOS transistors have independent variations. This is a
very hypothetical situation, since the Oxide Thickness should affect the PMOS and NMOS
transistors in the same way. The associated .PARAMDEX command would be as follows:
.PARAMDEX
+ M(PCH,TOX) SIG=2.5
+ M(NCH,TOX) SIG=2.5
Suppose now we are interested in intra-die variations. The statistical variations can be defined
as follows:
.PARAM TOX=0.015
.MCMOD NCH TOX DEV/GAUSS=0.0003
.MCMOD PCH TOX DEV/GAUSS=0.0003
It follows that the associated .PARAMDEX statements are:
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Eldo® User's Manual, 15.3