Fbb Cmos Tapered Buffer With Optimal Vth Selection

  • Harpreet Kaur Department of Electronics and Communication, Chitkara University, Himachal Pradesh-125001, India
  • Ajaypal Singh Department of Electronics and Communication, Chitkara University, Himachal Pradesh-125001, India
  • Lipika Gupta Department of Electronics and Communication, Chitkara University, Himachal Pradesh-125001, India
Keywords: Tapering factor, CMOS inverter, PDP, RBB, Average power, Threshold voltage


This paper represents fixed body biased CMOS Tapered Buffer which is designed to minimize the PDP (Power Delay Product) of the circuit. CMOS Tapered Buffers are often used for driving large capacitive load at high speed. Since there are tradeoffs between performance parameters of Buffer for minimizing its PDP value and due to technology constraints on the threshold voltage of MOS; one can vary the Vth up to certain limit while keeping the VDD constant. The proposed work is helpful in designing power efficient CMOS Tapered Buffer. This is found that in proposed Buffer when Vth value for the first stage of inverter is taken between the range of (0.2VDD - 0.4 VDD), its performance gets improved in terms of power dissipation. This analysis is verified by simulating the 2-stage Tapered buffer using standard 180nm CMOS technology in Cadence environment. Analysis performed on the schematic shows that FBB (Fixed Body Bias) Tapered Buffer reduces the average power dissipation across capacitive load by 77% and static power has been reduced to 18.3% at very less penalty in delay. Hence the proposed approach is suitable in the design of low power buffer for increasing the current capability of logic gate at optimal speed.


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How to Cite
Harpreet Kaur, Ajaypal Singh, & Lipika Gupta. (2014). Fbb Cmos Tapered Buffer With Optimal Vth Selection. Journal on Today’s Ideas - Tomorrow’s Technologies, 2(2), 93-105. https://doi.org/10.15415/jotitt.2014.22007