eldo_user

Optimization
Specifying Tracking with Design Variables
.CORREL EXPR ELEMENT={EXPRESSION}
Where ELEMENT can take the form of:
parameter_name
P(parameter_name)
P(subckt_name, subckt_parameter)
E(device_name, device_parameter)
M(model_name, model_parameter)
EM(device_name, model_parameter)
The character string EXPRESSION can contain references to E(), EM() and M(). These
quantities must be defined in the .PARAMOPT command.
Note
The ELEMENT should not be set as a design variable using the .PARAMOPT command.
Doing so would disable the .CORREL EXPR expression.
In the following case the .CORREL EXPR expression is disabled because P2 has been set as a
design variable with the .PARAMOPT command:
R1 1 0 P1
R2 2 0 P2
.PARAMOPT
+ P1=(1K, 1K, 100K)
+ P2=(5K, 5K, 500K) ! Incorrect
.CORREL EXPR P2=’1.2*P1’
In the following case P2 will not be affected by P1, but will track the value of the resistor R1:
R1 1 0 P1
R2 2 0 P2
.PARAMOPT P1=(1K, 1K, 100K)
.CORREL EXPR P2=E(R1,R)
The .CORREL EXPR command enables you to avoid having to edit files when an optimization
is performed on a non-parametric netlist. For example:
598
Eldo® User's Manual, 15.3