Recently, Intelligent IoT (IIoT), including various sensors, has gained significant attention due to its capability of sensing, deciding, and acting by leveraging artificial neural networks (ANN). Nevertheless, to achieve acceptable accuracy and high performance in visual systems, a power-delay-efficient architecture is required. In this paper, we propose an ultra-low-power processing in-sensor architecture, namely SenTer, realizing low-precision ternary multi-layer perceptron networks, which can operate in detection and classification modes. Moreover, SenTer supports two activation functions based on user needs and the desired accuracy-energy trade-off. SenTer is capable of performing all the required computations for the MLP's first layer in the analog domain and then submitting its results to a co-processor. Therefore, SenTer significantly reduces the overhead of analog buffers, data conversion, and transmission power consumption by using only one ADC. Additionally, our simulation results demonstrate acceptable accuracy on various datasets compared to the full precision models.
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Ocelli: Efficient Processing-in-Pixel Array Enabling Edge Inference of Ternary Neural Networks
Convolutional Neural Networks (CNNs), due to their recent successes, have gained lots of attention in various vision-based applications. They have proven to produce incredible results, especially on big data, that require high processing demands. However, CNN processing demands have limited their usage in embedded edge devices with constrained energy budgets and hardware. This paper proposes an efficient new architecture, namely Ocelli includes a ternary compute pixel (TCP) consisting of a CMOS-based pixel and a compute add-on. The proposed Ocelli architecture offers several features; (I) Because of the compute add-on, TCPs can produce ternary values (i.e., −1, 0, +1) regarding the light intensity as pixels’ inputs; (II) Ocelli realizes analog convolutions enabling low-precision ternary weight neural networks. Since the first layer’s convolution operations are the performance bottleneck of accelerators, Ocelli mitigates the overhead of analog buffers and analog-to-digital converters. Moreover, our design supports a zero-skipping scheme to further power reduction; (III) Ocelli exploits non-volatile magnetic RAMs to store CNN’s weights, which remarkably reduces the static power consumption; and finally, (IV) Ocelli has two modes, including sensing and processing. Once the object is detected, the architecture switches to the typical sensing mode to capture the image. Compared to the conventional pixels, it achieves an average 10% efficiency on its lane detection power consumption compared with existing edge detection algorithms. Moreover, considering different CNN workloads, our design shows more than 23% power efficiency over conventional designs, while it can achieve better accuracy.
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- NSF-PAR ID:
- 10426802
- Date Published:
- Journal Name:
- Journal of Low Power Electronics and Applications
- Volume:
- 12
- Issue:
- 4
- ISSN:
- 2079-9268
- Page Range / eLocation ID:
- 57
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3390/jlpea12040057
