Synergistic Die-Level Router for Multi-FPGA System with Time-Division Multiplexing Optimization
Jiarui Wang, Yanjing Liu, Yibo Lin · 2025
Modern multi-FPGA systems featuring multi-die devices connected through time-division multiplexing (TDM) techniques have become increasingly common as the scale of designs increases rapidly. FPGA designs are meticulously partitioned at die-level for prototyping in modern emulation systems. Conventional FPGA-level routers often result in a large critical connection delay that impacts the whole design’s frequency. Additionally, the excessive use of super long lines (SLLs) between neighboring dies leads to substantial routing congestion, causing the failure of the routing progress. To tackle these issues, we propose an effective and efficient die-level router for multi-FPGA systems, optimizing routing topology and the TDM ratio. Experimental results on the benchmarks from the die-level routing contest 2023 demonstrate 7.6% better critical connection delay with a $5.761 \times$ speed-up compared to the state-of-the-art router.