Abstract In imprecision-tolerant applications such as multimedia and signal processing a slightly degraded output quality is acceptable, which could lead to significant power reduction. We have proposed three approximate full adders for such applications. We have also considered the process variation impacts on approximate full adders for the first time. Twelve approximate full adders including ours have been used and analyzed in a ripple carry adder, as well as in a Sobel edge detection application. Experimental results show our design compared to the best existing approximate full adder reduces power consumption, delay and power-delay-product by 6.2%, 42.3% and 46.02%, respectively. Our proposed approximate ripple carry adder has the best performance in terms of error parameters, and the best PSNR (Peak signal-to-noise ratio) when used in Sobel algorithm. When the proposed approximate full adder is used in Sobel algorithm, it exhibits the least variability in terms of delay compared to other counterparts.

中文翻译：

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用于不精确容忍应用的过程变化感知近似全加器

摘要 在多媒体和信号处理等不精确容忍应用中，输出质量的轻微下降是可以接受的，这可能会导致显着的功耗降低。我们已经为此类应用提出了三个近似全加器。我们还首次考虑了工艺变化对近似全加器的影响。在纹波进位加法器以及 Sobel 边缘检测应用中，已经使用和分析了包括我们在内的 12 个近似全加器。实验结果表明，与现有的最佳近似全加器相比，我们的设计分别降低了 6.2%、42.3% 和 46.02% 的功耗、延迟和功率延迟积。我们提出的近似纹波进位加法器在误差参数方面具有最佳性能，以及在 Sobel 算法中使用时的最佳 PSNR（峰值信噪比）。当建议的近似全加器用于 Sobel 算法时，与其他对应物相比，它在延迟方面表现出最小的可变性。