SmartSpice Integration into the Cadence Design Framework

Since 1992, it has been possible to use SmartSpice within the Cadence Design Framework through the purchase from Cadence of an option known as the "HSPICE Plug". Unfortunately, the level of integration afforded by this option has been limited. With the advent of version 4.4 of Cadence Design Framework II, Cadence has made available their Open Analog Simulation Integration Socket (OASIS) interface, which provides access to internal subroutines within the Analog Artist Electrical Design System. Working closely with the OASIS group, Silvaco has taken advantage of this new interface, along with the Cadence SPICE Socket, to create a new and substantially tighter integration of SmartSpice with Analog Artist.

Under this new integration scheme, SmartSpice now explicitly appears in the Analog Artist simulator menu and Analog Artist now generates fully compatible SmartSpice netlists. Simulation within the Analog Artist environment is transparently performed by SmartSpice in batch mode,with full support for saving, plotting and marching variables. SmartSpice itself now generates results in Parameter Storage Format (PSF), which may be viewed in the Cadence Waveform Window. Cross-probing and back-annotation are fully supported via the Composer Design Entry tool.

This integration is now available in SmartSpice 1.5.2.R. However, users will need to purchase an OASIS Simulation Interface license from Cadence. The installation process is carried out with the command "SmartSpice -install", and is fully automated and self-verifying. A complete model library, SmartSpiceLib, is also distributed with SmartSpice. The library can be referenced via a "cds.lib" file, generated automatically with the command "smartspice -configure."

As an example of the SmartSpice/Analog Artist integration, Figure 1 shows a ring oscillator constructed in the Composer Design Entry tool from components of the SmartSpiceLib model library. This particular view is back-annotated with a set of node voltages at a single time point. In Figure 2 a plot of the output voltage as plotted in the Waveform Window is displayed and in Figure 3 a plot of the corresponding signal as plotted in SmartSpice is shown for comparison.

 

Figure 1. Schematic with SmartSpice components.

 

Figure 2. SmartSpice PSF output in the Waveform window.

 

Figure 3. Corresponding signal plotted directly in SmartSpice.