Reconfigurable MAC-Based Architecture for Parallel Hardware Implementation on FPGAs of Artificial Neural Networks

  • Nadia Nedjah
  • Rodrigo Martins da Silva
  • Luiza de Macedo Mourelle
  • Marcus Vinicius Carvalho da Silva
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 5164)


Artificial Neural Networks (ANNs) is a well known bio- inspired model that simulates human brain capabilities such as learning and generalization. ANNs consist of a number of interconnected processing units, wherein each unit performs a weighted sum followed by the evaluation of a given activation function. The involved computation has a tremendous impact on the implementation efficiency. Existing hardware implementations of ANNs attempt to speed up the computational process. However these implementations require a huge silicon area that makes it almost impossible to fit within the resources available on a state-of-the-art FPGAs. In this paper, we devise a hardware architecture for ANNs that takes advantage of the dedicated adder blocks, commonly called MACs to compute both the weighted sum and the activation function. The proposed architecture requires a reduced silicon area considering the fact that the MACs come for free as these are FPGA’s built-in cores. The hardware is as fast as existing ones as it is massively parallel. Besides, the proposed hardware can adjust itself on-the-fly to the user-defined topology of the neural network, with no extra configuration, which is a very nice characteristic in robot-like systems considering the possibility of the same hardware may be exploited in different tasks.


Neural Network Output Function Hardware Implementation Hardware Architecture Silicon Area 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2008

Authors and Affiliations

  • Nadia Nedjah
    • 1
  • Rodrigo Martins da Silva
    • 1
  • Luiza de Macedo Mourelle
    • 2
  • Marcus Vinicius Carvalho da Silva
    • 1
  1. 1.Department of Electronics Engineering and Telecommunication  
  2. 2.Department of System Engineering and Computation, Engineering FacultyState University of Rio de Janeiro 

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