eldo_user

Monte Carlo Analysis
Parameter Naming Conventions
As above, one may read this macro as follows: the random variable that affects the instance
parameter instance_parameter associated to the device device_name and such that its
distribution is specified in the definition of the parameter parameter_name.
Note that it may happen that on some devices there is no instance_parameter, there are only two
arguments in the macro. An example follows.
Macros EM(.) and M(.)
Here, consider a more elaborate netlist which uses a combination of local and global variations
on some model parameters of a bipolar junction transistor NPN. It represents a notable situation
where no implicit rule conflicts with the common sense.
The circuit is a Low Noise Amplifier. DEV and LOT variations are defined on the model
parameter ISS (saturated current for substrate junction), and the parasitic resistances parameters
RE, RB, and RC. 16 random variables are obtained:
• The global or LOT component for each model parameters: M(BIPNPN.NPNBIP,RB),
M(BIPNPN.NPNBIP,RC), M(BIPNPN.NPNBIP,RE), M(BIPNPN.NPNBIP,ISS). In
these macros there is no reference to local instances of subcircuits or devices. The model
cards are placed at the top level of a circuit.
• The local or DEV component for each instance of the subcircuit BIPNPN:
EM(XDUT.XDUT.XQ0.Q0,RB), EM(XDUT.XDUT.XQ0.Q0,RC),
EM(XDUT.XDUT.XQ0.Q0,RE), EM(XDUT.XDUT.XQ0.Q0,ISS),
EM(XDUT.XDUT.XQ1.Q0,RB), etc. The letter E means Element. The name of the
model is given, but is clearly associated to the given instance.
Syntax
The syntax of the M(.) macro is defined as follows:
M(model_name, model_parameter)
which may be interpreted as the random variable that affects the model parameter
model_parameter of the model model_name and such that its distribution is specified in the
definition of the parameter.
The syntax of the EM(.) macro is defined as follows:
EM(device_name, model_parameter)
You may read this macro as follows: the random variable that affects the model parameter
model_parameter of the device device_name and such that its distribution is specified in the
definition of the parameter.
Example
The complete netlist is provided below:
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Eldo® User's Manual, 15.3