Varicap threshold logic

ABSTRACT

In this paper, a highly compact novel Threshold Logic (TL) Gate approach called "Varicap TL (VcTL)" is proposed and described. The novel feature of the design is in using variable MOSFET capacitances which reduces the area. The electrical analysis of this variable MOSFET capacitance is presented and its variability is explained. Varicap TL (VcTL) gate is created by using a latch type decision circuit topology. Parallel counter implementations of (7,3) in 0.13µm and 0.18µm technology are realized by using proposed Varicap TL based on Minnick TL Network. Comparison of these implementations with Boolean Logic (BL) based dynamic (7,3) counter is shown. VcTL approach in 0.13µm offers 41% smaller area which is a significant result of the approach and 27% higher speed and only 24% higher power consumption compared to BL realization in 0.13µm technology. The results also show VcTL's scalability. As VcTL is scaled from 0.18µm to 0.13µm, the speed is increased by 21%, the area is decreased by 33% and power by 37%.

REFERENCES

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INDEX TERMS

Primary Classification:
  B. Hardware
  B.7 INTEGRATED CIRCUITS
      B.7.1 Types and Design Styles
          Subjects: VLSI (very large scale integration)

Additional Classification:
  B. Hardware
  B.6 LOGIC DESIGN
      B.6.1 Design Styles
          Subjects: Parallel circuits

General Terms:
Design, Performance, Verification

Keywords:
minnick tl network, parallel counter, threshold logic, variable capacitance