Low Power Approximate Adders

Introduction and Short Description

“lpACLib” is an open-source library for Low-Power Approximate Computing Modules (like adders and multiplier of different bit-widths).

It contains both synthesizable VHDL description and behavioral implementations in C (MATLAB implementations in progress). Besides our novel designs, it also contains implementations for several state-of-the-art arithmetic modules and their approximate versions and their area, power, and quality characterization. One of the key purposes of this open-source library is to facilitate research and development in approximate computing at higher abstraction levels, and to facilitate reproducible research and comparisons. For instance, these approximate arithmetic modules in different combinations can be used to develop novel approximate accelerators or more complex approximate circuits. This will also save precious research and development time, and will eliminate the huge amount of redundancy in the typical design work-flow of approximate blocks (the non-trivial task of re-implementing state-of-the-art)


In case of usage, please refer to our corresponding DAC 2016 publication:
Muhammad Shafique, Rehan Hafiz, Semeen Rehman, Walaa El-Harouni, Jörg Henkel, “A Low Latency Generic Accuracy Configurable Adder”, in 53nd ACM/EDAC/IEEE Design Automation Conference & Exhibition (DAC), 2016.


The “lpACLib” library contains the VHDL description of accurate and approximate versions of several arithmetic modules and accelerators. Moreover, it also provides the corresponding software behavioral models/implementations developed in C (MATLAB implementations in progress) to enable quality characterization.

This library contains the following components

Contributors: Authors, Vanshika Baoni, M. Abdullah Hanif

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