eldo_user

Eldo Netlist Setup
Subcircuits
.GLOBAL QWE
VG QWE 0 DC 3
*.SUBCKT with a global node name in argument list
.SUBCKT B QWE
R1 QWE 0 1K
.ENDS
V2 PIN2 0 DC 2
X2 PIN2 B
By default, Eldo will connect R1 between PIN2 and 0 because the symbolic subckt pin QWE is
related to real node PIN2.
When option DSCGLOB=GLOBAL is specified Eldo will connect R1 between global node
QWE and 0.
Multiplication (M) Factor
The M factor is an element multiplier, simulating the effect of multiple elements in parallel. The
M factor can be specified as a subcircuit parameter and applies to all elements.
For example, if you have a subcircuit defined and instantiated as follows:
.SUBCKT MYRSUB IN OUT
R1 IN 1 1000 M=4
R2 1 OUT 1000
.ENDS MYRSUB
X1 IN OUT MYRSUB M=2
By default, the resistances of X1.R1 and X1.R2 will be 125 Ω and 500 Ω respectively. It is
simulated as if there are eight X1.R1 devices in parallel and two X1.R2 devices in parallel. As
can be seen in the example, the M factor works through the hierarchy. When it is specified on a
subcircuit instance (X instance), every element defined in the subcircuit will be duplicated by
this multiplication factor.
You should not specify an M factor value less than 1 on devices as this could lead to simulating
devices that cannot be physically realized. However, specifying M=0 on a subcircuit instance
means the M factor is ignored for that subcircuit.
To change the M factor behavior, so that the M=val factor of a subcircuit instance is handled as
a user-defined parameter instead of a multiplication factor, specify the M53 option. In the
previous example, with M53 specified, the final resistances of X1.R1 and X1.R2 will be 250 Ω
and 1000 Ω, respectively. It is simulated as if there are four X1.R1 devices in parallel.
See Also
• Subcircuit Instance in the Eldo Reference Manual
• .SUBCKT in the Eldo Reference Manual
• .GLOBAL in the Eldo Reference Manual
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Eldo® User's Manual, 15.3