TCN-CUTIE: A 1036 TOp/s/W, 2.72 uJ/Inference, 12.2 mW All-Digital Ternary Accelerator in 22 nm FDX Technology

TL;DR

This paper presents TCN-CUTIE, a fully digital ternary neural network accelerator in 22 nm FDX technology, achieving high energy efficiency and low power for TinyML applications, supporting both TNN and TCN models.

Contribution

The work introduces a flexible, all-digital TNN accelerator supporting TCNs with extensions, achieving state-of-the-art energy efficiency and power consumption in TinyML scenarios.

Findings

Achieves 1036 TOp/s/W peak energy efficiency.

Supports TNN and TCN with high accuracy.

Operates at 12.2 mW power consumption.

Abstract

Tiny Machine Learning (TinyML) applications impose uJ/Inference constraints, with a maximum power consumption of tens of mW. It is extremely challenging to meet these requirements at a reasonable accuracy level. This work addresses the challenge with a flexible, fully digital Ternary Neural Network (TNN) accelerator in a RISC-V-based System-on-Chip (SoC). Besides supporting Ternary Convolutional Neural Networks, we introduce extensions to the accelerator design that enable the processing of time-dilated Temporal Convolutional Neural Networks (TCNs). The design achieves 5.5 uJ/Inference, 12.2 mW, 8000 Inferences/sec at 0.5 V for a Dynamic Vision Sensor (DVS) based TCN, and an accuracy of 94.5 % and 2.72 uJ/Inference, 12.2 mW, 3200 Inferences/sec at 0.5 V for a non-trivial 9-layer, 96 channels-per-layer convolutional network with CIFAR-10 accuracy of 86 %. The peak energy efficiency is 1036 TOp/s/W, outperforming the state-of-the-art silicon-proven TinyML quantized accelerators by 1.67x while achieving competitive accuracy.