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Approximate Hardware Generation Using Formal Techniques

  • Saman Froehlich
  • Daniel Große
  • Rolf Drechsler
Chapter

Abstract

When it comes to the design of hardware for approximate computing, the exactness requirement between a specification of a circuit and its implementation is relaxed. In this chapter we present two different methods to generate approximate hardware for a given specification and its non-approximated implementation. We use formal techniques to guarantee that bounds for application specific error-metrics hold.

The first method for approximate hardware generation is an exact BDD-based technique, which focuses on single-output functions. Due to the complexity of the problem, scalability is an issue. For this reason, we further present a heuristic approach, which uses Symbolic Computer Algebra to determine the error-metric. This approach is tailored for arithmetic circuits. We apply this method to Ripple-Carry-Adders and compare the results to state-of-the-art handcrafted approximate hardware.

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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • Saman Froehlich
    • 1
  • Daniel Große
    • 1
    • 2
  • Rolf Drechsler
    • 1
    • 2
  1. 1.Cyber-Physical Systems, DFKI GmbHBremenGermany
  2. 2.Group of Computer ArchitectureUniversity of BremenBremenGermany

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