Cadence Mixed-Signal Circuit Design Environment User Guide
Running a Mixed-Signal Simulation
October 2003
172
Product Version 5.0
Analog Stimulus File
In HNL, use the analog stimulus file to connect stimuli to only the nets in the top-level
cellview. This requirement is imposed by used circuit simulator because stimuli may not be
allowed to connect to nets embedded in lower levels of the design hierarchy. Mapping nets or
instance names in lower levels of the design hierarchy, however, is allowed.
For example, if in<3:0> and control are signals existing in the top-level cellview, you can use
voltage sources to drive [#/in<3>] and [#/control] in the stimulus file, as shown in the following
example:
*comment, inst /inst<1> is mapped to [$/inst<1>]
*comment, inst /a/b is mapped to [$/a/b]
*comment, net /a/net<1> is mapped to [#/a/net<1>]
v0 [#/in<3>] 0 dc 5v
v1 [#/control] 0 dc 3v
Note: Analog stimuli supplied by an analog stimulus file can drive only analog nets and
interface nets. Attempts to drive or refer to digital nets with analog stimuli in the stimulus file
will generate errors.
To generate an analog stimulus file
1. From the Simulation window, choose Setup Stimulus Edit Analog (or Setup
Stimuli Analog if you are using the SpectreVerilog simulator).
The Edit Stimulus File form is displayed.
The Cadence® Analog Design Environment User Guide contains information about
entering analog stimuli. See The Analog Stimuli File for direct simulation or Stimuli Setup
for socket simulation.
For mixed-signal socket simulation, only text-file entry is currently available. In the Edit
Stimulus File form, choose Text Editor, enter the text file name, and click OK.
For mixed-signal direct simulation (SpectreVerilog), you can generate an analog stimulus
file through the Setup Analog Stimuli form, or you can provide the analog stimulus in a
text file. The information you enter on the Setup Analog Stimuli form is converted to a
stimulus file. See The Analog Stimuli File for information on specifying a text file as the
stimulus file for direct simulation.
2. Make any stimulus changes necessary for this simulation.
You must use the analog simulator language to define the analog stimuli. File syntax is
compatible with the Cadence® analog circuit design environment.
3. Change signal and instance names to Cadence® analog circuit design environment
naming conventions.