• Transactions on Semiconductor Engineering
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• v.2 no.4
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• pp.78-83
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• 2024

As the integration of multiple systems into a single chip increases, on-chip bus power consumption has become a significant concern, necessitating strategies to reduce it. In contrast, off-chip environments requiring reduced energy consumption on buses primarily utilize the Data Bus Inversion (DBI) technique. DBI is a data encoding method that reduces switching activity, achieving an average reduction of 18.25% in switching activity and effectively lowering total energy consumption in off-chip applications. However, applying conventional DBI on-chip leads to energy overhead issues, highlighting the need for a novel DBI encoder tailored to on-chip environments. This paper proposes an approximate DBI encoder that incorporates approximate computation into the majority voter circuit, a key component of the DBI encoder, to address the energy overhead issue. The DBI technique using the two proposed approximate majority voter circuits reduces average switching activity by 5.75% and 10.50%, respectively. While the approximate computation results in a slight increase in switching activity compared to the conventional DBI, it achieves an average reduction of approximately 20% in delay time and around 56% in power consumption.