A Bootstrapped Switch for nMOS Reversible Energy Recovery Logic for Low-Voltage Applications

Seokkee KIM  Soo-Ik CHAE  

IEICE TRANSACTIONS on Electronics   Vol.E89-C   No.5   pp.649-652
Publication Date: 2006/05/01
Online ISSN: 1745-1353
DOI: 10.1093/ietele/e89-c.5.649
Print ISSN: 0916-8516
Type of Manuscript: LETTER
Category: Electronic Circuits
bootstrapped nMOS switch,  nMOS reversible energy recovery logic (nRERL),  adiabatic microprocessor,  

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In this paper, we describe a bootstrapped nMOS switch that is modified to reduce leakage current for nMOS reversible energy recovery logic (nRERL) [1]. Conventional bootstrapped switches are not suitable for nRERL because they have nonadiabatic loss due to leakage current that flows while boosted. Therefore, we lowered the gate voltage of the isolation transistor in each bootstrapped switch to reduce this leakage current. With detailed analysis and simulation, we determined the range of the bias voltage, in which the switches can transfer full-swing input signals. We implemented a simple 8-bit nRERL microprocessor into silicon and measured its energy consumption to confirm our analysis. For the supply voltage of 1.8 V and the operating frequency of 880 kHz, we found that the microprocessor consumed about 8.5 pJ/cycle for 1.3 V < Vbias <1.6 V, which was just about a half of its energy consumption when Vbias = 1.7 V.