In VLSI, RC Co-efficient file contains information about resistance (R) and capacitance (C) values associated with the interconnects and components in an integrated circuit.
Resistance (R): We know that resistance means the opposition encountered by electric current as it flows through a conductor. In the context of RC coefficient files, resistance values are assigned to various metal interconnects and other conductive paths that link different components, such as transistors and gates on the chip. The resistance values help estimate the power dissipation and voltage drop along the interconnects, which are crucial considerations for ensuring proper signal integrity and minimizing power losses in the chip.
Capacitance: capacitance in VLSI refers to the ability of a structure or material to store an electric charge. In context of RC coefficient files, capacitance values are assigned to various metal layers and other structures, such as gates and diffusion regions, within the chip. These capacitance values play a crucial role in estimating the charging and discharging times of nodes, which directly affect the overall performance and speed of the circuit.
RC Extraction: RC extraction is a critical step in the PD. It involves the process of determining the resistance and capacitance values of the various interconnects and components based on the layout info. The SPEF(Standard Parasitic Extraction Format) file is generated as an output of this extraction.
Before RC Extraction: Before RC Extraction, capTables or Quick RC file (QRC files) are used to estimate the design resistance and capacitance values. These files are inaccurate compared to SPEF file.
Usage of RC Co-efficient file: The RC coefficient file is using in various stages. It is mainly using for timing analysis, power analysis and Signal integrity.
