eldo_user

Eldo Control Language
.STEP Alternative
.define_testbench tb_netlist (param_tb_value = 1 )
2. Modify the original netlist to exclude the .STEP and modify the .PARAM command to
use the testbench argument:
.param p = param_tb_value
.end_define_testbench
3. Define an ECL task with a step loop to run the simulations. This is an incremental loop;
the parameter being swept, loop_param, is specified with param. The start, stop, and
step define the loop structure. The loop ends with the endstep command.
.define_task t1
/* parameter for the step loop. */
set loop_param = 1
set wave_res[] = 0
/* step loop similar to the .step command. */
step (type=step, param=loop_param, start=1k, stop=200k, step=1k)
/* run the simulation. */
simulation(tb_netlist(param_tb_value=loop_param),
+ name="res/simu" + loop_param + ".cir",
+ wave_res[loop_param/1k]=@res_wave)
endstep
.end_define_task
.t1
The full example is located in $MGC_AMS_HOME/examples/ecl/25-step_alternative.
The simulation command runs the simulation of the testbench and obtains results. The
simulation files and waveforms for each step will be generated in different files in the output
directory res. The name of each file is made up of the simu prefix followed by the step index
(simu1, simu2, simu3, and so on). These generated files can be useful to debug simulations. A
directory has been specified so that all generated temporary files can be easily removed. The
testbench is instantiated with the .t1 statement.
An important difference to note compared with a regular .STEP is:
With the original netlist, compound waveforms are generated; but with ECL, since there are 200
simulations, by default 200 wdb files will be generated; if the same wdb is used, it will be
overwritten. To avoid this, there are two solutions:
• Specify a specific name for each wdb file (using the “name” argument).
Avoid this solution, because you will have 200 wdb files generated.
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Eldo® User's Manual, 15.3