Interconnect

Definition: Interconnect in VLSI refers to the metal wires that connect various components and devices on an integrated circuit.

Key Points:

  • Critical for signal transmission and power distribution
  • Multiple layers of metal used in modern ICs
  • Significant impact on chip performance and power consumption

Types:

  • Local: Short connections within a circuit block
  • Global: Long-distance connections across the chip
  • Power and Ground: For power distribution

Challenges:

  • RC delay in long interconnects
  • Crosstalk between adjacent wires
  • Electromigration in high-current paths

Design Considerations:

  • Wire width and spacing
  • Metal layer selection
  • Repeater insertion for long paths

Importance:

  • Can dominate circuit delay in advanced nodes
  • Affects power consumption and signal integrity
  • Key factor in physical design and timing closure

Efficient interconnect design is crucial for high-performance, low-power VLSI circuits.