Accounting for the skin effect during repeater insertion

ABSTRACT

Since the skin effect will increase the propagation delay in an interconnect, it will also affect how to optimally select the number and size of the buffers. Failing to include the skin effect during buffer design may result in as much as 35% extra delay compared to the optimal repeater chain. We present a new method with closed-form expressions for repeater insertion where we take into account the skin effect and also the relationship between interconnect resistance, capacitance and inductance that are determined from the geometrical parameters. We also investigate the skin-effect influence on power dissipation for an optimally designed repeater chain, and find that the increase is at most 10% of the dynamic power dissipation.

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INDEX TERMS

Primary Classification:
  B. Hardware
  B.7 INTEGRATED CIRCUITS
      B.7.2 Design Aids

General Terms:
Design, Performance

Keywords:
buffer design, delay, optimization, power, repeater insertion, skin effect