Fine-grain reconfigurable logic cells based on double-gate CNTFETs

ABSTRACT

This paper presents 2-inputs cells designed to perform reconfigurable operations in nanometric systems exploiting the ambipolar property of double-gate (DG) carbon nanotube (CNT) FETs. Previous work [1] described a dynamic logic cell generating only 14 functions instead of 16 normally performed by the multiplexer-based logic part of a CLB (Configurable Logic Block) of an FPGA for 2-inputs. In this work, a reconfigurable 2-input dynamic logic cell designed using DG-CNTFET devices is able to achieve the whole set of 16 functions exploiting a specific correlation between input and configuration signals to offer full functionality over previous version. We also built a reconfigurable 2-input static logic cell which performs 16 functions. Both cells demonstrate a significant reduction in circuit complexity with respect to conventional CMOS-based reconfigurable cells for equivalent functionality. Compared with a 2-LUT, the dynamic cell improve the time delay by a factor of 2X to the detriment of 2X increase in power consumption, while the static logic cell shows an improvement of 2X in term of power consumption and time delay.

References

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Index Terms

• Hardware

  • Emerging technologies

  • Integrated circuits

    • Logic circuits

      • Combinational circuits

  • Very large scale integration design

    • Application-specific VLSI designs