Has anyone here tried Ansoft Nexxim ?
**broken link removed**
"U-Chip evaluated the performance of several commercial simulators before selecting Nexxim. Benchmarks performed on a memory cell with 47,500 transistors established the clear advantages provided by Ansoft technology with results that matched measurements within 1 percent. One well-known SPICE simulator, while providing transistor-level accuracy, failed to handle the large transistor count. Two commonly used fast-SPICE simulators offered the capacity, but predicted incorrect DC solutions and distorted transient waveforms after the first few clock cycles. "We must have confidence in our circuit simulator before we can commit to silicon," says Juei-Lung Chen. "Fast-SPICE simulators are not fast at all if you end up re-spinning the chip."