Analysis and Compensation of the Effects of Analog VLSI Arithmetic on the LMS Algorithm

作者：Carvajal Gonzalo^*; Figueroa Miguel; Sbarbaro Daniel; Valenzuela Waldo

来源：IEEE Transactions on Neural Networks, 2011, 22(7): 1046-1060.

DOI：10.1109/TNN.2011.2136358

• Analog very large scale integration
• least-mean-square algorithm
• on-chip learning
• silicon neural networks

Analog very large scale integration implementations of neural networks can compute using a fraction of the size and power required by their digital counterparts. However, intrinsic limitations of analog hardware, such as device mismatch, charge leakage, and noise, reduce the accuracy of analog arithmetic circuits, degrading the performance of large-scale adaptive systems. In this paper, we present a detailed mathematical analysis that relates different parameters of the hardware limitations to specific effects on the convergence properties of linear perceptrons trained with the least-mean-square (LMS) algorithm. Using this analysis, we derive design guidelines and introduce simple on-chip calibration techniques to improve the accuracy of analog neural networks with a small cost in die area and power dissipation. We validate our analysis by evaluating the performance of a mixed-signal complementary metal-oxide-semiconductor implementation of a 32-input perceptron trained with LMS.

• 出版日期2011-7