eldo_user

Optimization
Types of Design Objective
Types of Design Objective
This section describes the different types of design objectives that will be considered by the
.OPTIMIZE command when conducting an optimization.
It covers:
Minimization and Maximization Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 610
Goal Values Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 612
Range Constraints Objectives. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 614
Objectives for Operating Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 616
Minimization and Maximization Objectives
This topic explains how to specify design objectives that minimize or maximize extracted
measures.
Note
Optimization in Eldo always minimizes. Maximizing f(x) is handled as minimizing -f(x).
Objectives that minimize measures are specified using the .OBJECTIVE command as follows:
* Minimize or Maximize statements
.OBJECTIVE EXTRACT_INFO LABEL=f_m
+ {$MACRO|FUNCTION}
+ GOAL=MINIMIZE
+ [WEIGHT=MU_M]
The optional weight μ m is a positive number, defaulting to one.
Multiple Specifications of Minimization Objectives
The syntax enables .OBJECTIVE command statements to be specified multiple times in the
netlist. If several objectives are qualified as GOAL=MINIMIZE (or MAXIMIZE), a weighted
objective function is built as the summation of all these particular measures. The optimizer
minimizes a unique objective that is the weighted sum of the whole objectives. Consider the
following:
* Aggregation of two Minimize statements
.OBJECTIVE EXTRACT_INFO_1 LABEL=F_M_1
+ {$MACRO|FUNCTION}
+ GOAL=MINIMIZE WEIGHT=MU_M_1
.OBJECTIVE EXTRACT_INFO_2 LABEL=f_M_2
+ {$MACRO|FUNCTION}
+ GOAL=MINIMIZE WEIGHT=MU_M_2
610
Eldo® User's Manual, 15.3