Abstract
Approximate computing relaxes accuracy, enhance efficiency, and benefit in terms of area. It is widely popular in emerging applications like mining, search, vision, recognition where inaccuracies are tolerable. This tolerance towards errors is exploited to design circuits. The most crucial stage is to strike the proper balance between error and output quality. A systematic framework is used for generating approximate circuits with a specific error guarantee. The key idea is to use the property checking technique based on SAT to compute the worst-case error. In this design method Look-up Table (LUT) is used to acquire approximation with worst-case error metric as a constraint. A novel technique is proposed to select nodes for insertion of LUTs is discussed. The method evolved around toggle count and observability of nodes in the circuit. The number of transistors used, and errors is examined for analysis. This analysis will help in evaluating the output of the adder circuit obtained through approximation. This method was implemented using Yosys and evaluated adder circuit. The aim of this paper is to adopt formal methods such as satiability solvers for analysis of approximate adder circuits. When the worst-case absolute error and area are taken into account for 64 bit, 32 bit and 16 bit our solution will provide a superior trade-off.
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Chippa, V.K., Chakradhar, S.T., Roy, K., Raghunathan, A.: Analysis and characterization of inherent application resilience for approximate computing. In: Proceedings of the 50th Annual Design Automation Conference, pp. 1–9 (2013)
Kulkarni, P., Gupta, P., Ercegovac, M.D.: Trading accuracy for power in a multiplier architecture. J. Low Power Electron. 7(4), 490–501 (2011)
May, D., Stechele, W.:Voltage over-scaling in sequential circuits for approximate computing. In: 2016 International Conference on Design and Technology of Integrated Systems in Nanoscale Era (DTIS), pp. 1–6. IEEE (2016)
Venkataramani, S., Chakradhar, S.T., Roy, K., Raghunathan, A.: Computing approximately, and efficiently. In: 2015 Design, Automation & Test in Europe Conference & Exhibition (DATE), pp. 748–751. IEEE (2015)
Venkatesan, R., Agarwal, A., Roy, K., Raghunathan, A.: MACACO: modeling and analysis of circuits for approximate computing. In: IEEE/ACM International Conference on Computer-Aided Design (IC- CAD), San Jose, CA, pp. 667–673 (2011)
Nepal, K., Li, Y., Bahar, R.I., Reda, S.: ABACUS: a technique for automated behavioral synthesis of approximate computing circuits, InL Design, Automation and Test in Europe Conference & Exhibition (DATE), Dresden, pp. 1–6 (2014)
Ceška, M., Matyáš, J., Mrazek, V., Sekanina, L., Vasicek, Z., Vojnar, T.: ADAC: automated design of approximate circuits. In: CAV. LNCS, vol. 10981, pp. 612–620. Springer, Cham (2018)
Ranjan, A., Raha, A., Venkataramani, S., Roy, K., Raghunathan, A.: ASLAN: synthesis of approximate sequential circuits. In: Design, Automation Test in Europe Conference & Exhibition (DATE), Dresden, pp. 1–6 (2014)
Gupta, V., et al.: Low-power digital signal processing using approximate adders. IEEE Trans. Comput.-Aided Des. Integr. Circuits Syst. 32(1), 124–137 (2012)
Venkataramani, S., Sabne, A., Kozhikkottu, V., Roy, K., Raghunathan, A.: SALSA: systematic logic synthesis of approximate circuits. In: DAC Design Automation Conference, pp. 796–801 (2012)
Venkataramani, S., Roy, K., Raghunathan, A.: Substitute-and-simplify: a unified design paradigm for approximate and quality configurable circuits. In: 2013 Design, Automation & Test in Europe Conference & Exhibition (DATE), pp. 1367–1372. IEEE (2013)
Češka, M., Matyáš, J., Mrazek, V., Sekanina, L., Vasicek, Z., Vojnar, T.: Approximating complex arithmetic circuits with formal error guarantees: 32-bit multipliers accomplished. In: 2017 IEEE/ACM International Conference on Computer-Aided Design (ICCAD), pp. 416–423. IEEE (2017)
Češka, M., Matyáš, J., Mrazek, V., Sekanina, L., Vasicek, Z., Vojnar, T.: ADAC: automated design of approximate circuits. In: International Conference on Computer Aided Verification, pp. 612–620. Springer, Cham (2018)
Jo, S., Matsumoto, T., Fujita, M.: SAT-based automatic rectification and debugging of combinational circuits with LUT insertions. IPSJ Trans. Syst. LSI Design Methodol. 7, 46–55 (2014)
Vinod, G. U., V. S. Vineesh, Jaynarayan T. Tudu, Masahiro Fujita, and Virendra Singh.: LUT-based Circuit Approximation with Targeted Error Guarantees. In 2020 IEEE 29th Asian Test Symposium (ATS), IEEE, pp. 1–6, (2020)
Lingamneni, A., Enz, C., Nagel, J.-L., Palem, K., Piguet, C.: Energy parsimonious circuit design through probabilistic pruning. In: 2011 Design, Automation & Test in Europe, IEEE, pp. 1–6 (2011)
Mirzaie, N., Seyyed Mahdavi, S.J., Mohammadi, K.: Evolving more testable digital combinational circuits. In: CDES, pp. 40–45 (2010)
Jiang, H., Han, J., Lombardi, F.: A comparative review and evaluation of approximate adders. In: Proceedings of the 25th Edition on Great Lakes Symposium on VLSI, pp. 343–348 (2015)
Acknowledgment
This work is supported by Visvesvaraya Ph.D. Scheme, Meity, Govt. of India. MEITY-PHD-2950.
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Choudhary, P., Bhargava, L., Fujita, M., Singh, V. (2022). Synthesis of LUT Based Approximating Adder Circuits with Formal Error Guarantees. In: Shah, A.P., Dasgupta, S., Darji, A., Tudu, J. (eds) VLSI Design and Test. VDAT 2022. Communications in Computer and Information Science, vol 1687. Springer, Cham. https://doi.org/10.1007/978-3-031-21514-8_36
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DOI: https://doi.org/10.1007/978-3-031-21514-8_36
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