RTLtoGDSII

RTLtoGDSII refers to the end-to-end process of converting a digital design described at the register-transfer level (RTL) into a GDSII layout database that can be used for semiconductor fabrication. The flow bridges the front-end design phase, where RTL code and test benches are developed and simulated, with the back-end physical design phase, where a physical layout is created and prepared for manufacturing.

A typical RTLtoGDSII flow includes several stages. RTL design is written in hardware description languages such as Verilog or VHDL and verified through functional and timing simulations. Synthesis translates the RTL into a gate-level netlist mapped to a target technology library of standard cells. The design is then floorplanned and subjected to placement and routing to meet area, timing, and power constraints. Clock tree synthesis, routing optimization, and parasitic extraction are performed, followed by timing analysis and sign-off checks. Throughout, physical verification ensures design rule checks (DRC) and layout versus schematic (LVS) consistency. The final step is generating the GDSII database, the standard mask layout format used for fabrication, often with accompanying reports and metadata.

Key considerations in RTLtoGDSII include library availability, process design kits (PDKs), timing/power trade-offs, and design rule compliance. The flow may vary between full-custom, standard-cell, or mixed-technology designs and between ASIC and FPGA workflows. The resulting GDSII file represents the finalized layout geometry, routing, and layers required to manufacture the integrated circuit.