Parallel SmartSpice for PC
Introduction
Parallel SmartSpice version 1.5.4 is now available on multiple CPU Pentium PCs. The parallel version of SmartSpice allows single SPICE simulations to be executed on multiple CPUs. This provides significant run time speed improvements over traditional single CPU execution. (Figure 1)

Figure 1. Speedup on two Pentium II CPU's for MCNC benchmark circuits
Parallel SmartSpice for the first time now allows PC users to efficiently run large IC and PCB SPICE simulations in a fraction of the time required for single CPU simulation. This unique software solution provides designers with the ability to take advantage of the available multi-processor PCs.
Parallel SmartSpice for PCs is currently available running under the Linux operating system. Linux is a UNIX clone which runs on Pentium based PCs. It has all the features of a modern UNIX, including multiple CPU capabilities. An NT based version of Parallel SmartSpice is planned for release in Q2.
Parallel SPICE Implementation
The Linux implementation of Parallel SmartSpice release 1.5.4 offers the same functionality as Parallel SmartSpice running on UNIX machines. The models that are parallelized to take advantage of the availability of multiple CPUs on PC platforms are listed in Table 1. The sparse matrix factorization which occurs at every iteration is also parallelized.
| Model | Version | Level |
| BSIM1 | - | level 13 |
| BSIM3 | version 2 | level 47 |
| BSIM3 | version 3.0 | level 49,11,8 |
| BSIM3 | version 3.1 | level 49,11,8 |
| MOS123 | - | level 1,2,3 |
| BJT | - | - |
| TSMC | - | level 18,28 |
The accuracy of the sequential implementation for all of these models is maintained. SmartSpice will exhibit the same behavior irrespective of the number of processors that are used. In other words, the parallelization is entirely transparent as far as the user is concerned.
Parallel SmartSpice Performance
Figure 1 presents the run time speedup for a series of test circuits obtained using a dual processor Pentium II machine running at 300 Mhz. The results show an average speedup of 1.7 on two CPUs. The four circuits are part of the University of North Carolina MCNC benchmark suite and use Silvaco's implementation of the BSIM3v3 model (Level 8) . The size of the circuits range from 942 to 13880 devices. In further experiments, we found that a dual processor Pentium II running at 300Mhz is very competitive with the performance of leading UNIX workstations.
Previous Silvaco publications including 'Simulation Standard' (Volume 8, Number 5, May 1997) and 'TCAD Driven CAD' (Volume 8, Number 7, July 1997) discuss in detail the different steps of the parallelization process, and present performance results on UNIX platforms.
Conclusion
Efficiency and affordability are the key words that best describe Parallel SmartSpice for multi-processor PCs. This product uniquely offers a low cost / high speed circuit simulation solution that provides comparable performance, and preserves all of the industry leading functionality and convergence properties of the workstation version.