1. Circuit Simulation: The project is to analyze and verify VLSI systems via full circuit simulation and to demonstrate vastly improved scalability in order to raise the quality and scope of predictive circuit modeling. VLSI circuit simulation has become critical due to interconnect dominance of advanced fabrication technologies. Functional modules are integrated through substrates and connected by wires with parasitics. A simulation of the whole system will empower designers with a full grasp of the transient behavior of the circuits. Approaches: We have tried various matrix solvers, alternating direction integration and distributed computation. Recently, we adopt matrix exponential method using Krylov subspace for numerical integration. The method allows high order integration with dynamically optimized coeficients and thus does not belong to the class of conventional linear multistep methods.
2. VLSI Physical Layout: The project is to synthesize VLSI physical layout in terms of placement and routing. In theory, the layout problems are NP complete. In practice, the advance of VLSI design calls for high quality solutions with fast turnaround on circuits of many millions of objects. Approaches: We have tried resistive network analogy, partitioning, eigenvalue/eigenvector approaches for placement. Recently, we propose an ePlace method using electronic charge analogy for placement. The electronic potential and repulsive charge force provide a global view of the cell density distribution. Morevoer, we are able to use fast Fourier transform to solve Poisson equations with efficiency. The results become the record keeper of most of the benchmarks.
3. High Performance Interconnect: The project is to push the performance envelopes in terms of the signal latency, bandwidth, and power conumption for on-chip and off-chip interconnect.
4. Medical Imaging: The project is to analyze MEG, EEG, ECG and BCG for diagnosis and human machine interface. We classify cases such as schizophrenia, PTSD, and tinnitus.