Designing Approximate Arithmetic Circuits with Combined Error Constraints

conference paper

English

Approximate circuits trading the power consumption for the quality of results play a key role in the development of energy-aware systems. Designing complex approximate circuits is, however, a very difficult and computationally demanding process. When deploying approximate circuits, various error metrics (e.g., mean average error, worst-case error, error rate), as well as other constraints (e.g., correct multiplication by~0), have to be considered. The state-of-the-art approximation methods typically focus on a single metric which significantly limits the  applicability of the resulting circuits. In this paper, we experimentally investigate how various error metrics and their combinations affect the reduction of the power consumption that can be achieved. To this end, we extend evolutionary-driven techniques that allow us to  effectively explore the design space of the approximate circuits. We identify principal limitations when complex error constraints are required as well as important correlations among the error metrics enabling the construction of circuits providing the best-known trade-offs between the power reduction and combined error constraints.

approximate circuit, evolutionary design, error metrics

ČEŠKA, M.; MATYÁŠ, J.; MRÁZEK, V.; VOJNAR, T.

31. 8. 2022

Institute of Electrical and Electronics Engineers

Gran Canaria

978-1-6654-7404-7

Proceeding of 25th Euromicro Conference on Digital System Design 2022 (DSD'22)

785

792

8