Driver pre-emphasis techniques for on-chip global buses

ABSTRACT

By using current-sensing differential buses with driver pre-emphasis techniques, power dissipation is reduced by 26.0% - 51.2% and peak current is reduced by 63.8%, compared to conventional repeater insertion techniques, for 10mm long buses in TSMC 0.25μm technology. This proposed architecture lowers the worst coupling capacitance to total capacitance ratio to 14.4%. It only requires 7.9% more bus routing area than single-ended designs for a 16-bit bus, and saves all of the repeater placement blockages. To further verify that the driver pre-emphasis techniques can also be applied to voltage-mode single-ended buses, a test chip in TSMC 0.18μm technology was fabricated and measured

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INDEX TERMS

Primary Classification:
  B. Hardware
  B.4 INPUT/OUTPUT AND DATA COMMUNICATIONS
      B.4.3 Interconnections (subsystems)
          Subjects: Topology (e.g., bus, point-to-point)

General Terms:
Design, Performance

Keywords:
crosstalk, current sensing, differential, low-power, on-chip bus, peak current, pre-emphasis