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arXiv · 2412.14051

Circuits-Informed Machine Learning Technique for Blind Open-Loop Digital Calibration of SAR ADC

Sumukh Bhanushali·Debnath Maiti·Phaneendra Bikkina·Esko Mikkola·Arindam Sanyal
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Abstract

This work presents a supervised machine-learning (ML) approach for blind digital calibration of SAR ADCs without requiring prior knowledge of errors. A low-speed reference ADC is used to train a shallow neural network (NN) to estimate errors in a high-speed ADC by comparing the outputs of the ADCs when their sampling instants align and subtracting these errors in the back-end. The proposed NN-calibration improves SFDR of a 28nm, 12-bit, 84MHz ADC by >38dB while consuming 25.8fJ/conversion-step.

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Sumukh Bhanushali, Debnath Maiti, Phaneendra Bikkina, Esko Mikkola, Arindam Sanyal. 2024-12-18. Circuits-Informed Machine Learning Technique for Blind Open-Loop Digital Calibration of SAR ADC. https://arxiv.org/abs/2412.14051

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