Utilizing reverse short channel effect for optimal subthreshold circuit design

ABSTRACT

The impact of the Reverse Short Channel Effect (RSCE) on device current is stronger in the subthreshold region due to the reduced Drain-Induced-Barrier-Lowering (DIBL) and the exponential dependency of current on threshold voltage. This paper describes a device size optimization method for subthreshold circuits utilizing RSCE to achieve high drive current, low device capacitance, less sensitivity to random dopant fluctuations, and better subthreshold swing. Simulation results using ISCAS benchmark circuits show that the critical path delay and power consumption can be improved by up to 10.4% and 34.4%, respectively.

REFERENCES

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INDEX TERMS

Primary Classification:
  B. Hardware
  B.7 INTEGRATED CIRCUITS
      B.7.1 Types and Design Styles

General Terms:
Design, Performance

Keywords:
PVT variations, digital circuits, optimization, reverse short channel effect, subthreshold circuits, subthreshold operation