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As the number of weight parameters in deep neural networks (DNNs) continues growing, the demand for ultra-efficient DNN accelerators has motivated research on non-traditional architectures with emerging technologies. Resistive Random-Access Memory (ReRAM) crossbar has been utilized to perform insitu matrix-vector multiplication of DNNs. DNN weight pruning techniques have also been applied to ReRAM-based mixed-signal DNN accelerators, focusing on reducing weight storage and accelerating computation. However, the existing works capture very few peripheral circuits features such as Analog to Digital converters (ADCs) during the neural network design. Unfortunately, ADCs have become the main part of power consumption and area cost of current mixed-signal accelerators, and the large overhead of these peripheral circuits is not solved efficiently. To address this problem, we propose a novel weight pruning framework for ReRAM-based mixed-signal DNN accelerators, named TINYADC, which effectively reduces the required bits for ADC resolution and hence the overall area and power consumption of the accelerator without introducing any computational inaccuracy. Compared to state-of-the-art pruning work on the ImageNet dataset, TINYADC achieves 3.5× and 2.9× power and area reduction, respectively. TINYADC framework optimizes the throughput of state-of-the-art architecture design by 29% and 40% in terms of the throughput per unit of millimeter square and watt (GOPs/s×mm 2 and GOPs/w), respectively.
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ReBoc: Accelerating Block-Circulant Neural Networks in ReRAM
Deep neural networks (DNNs) emerge as a key component in various applications. However, the ever-growing DNN size hinders efficient processing on hardware. To tackle this problem, on the algorithmic side, compressed DNN models are explored, of which block-circulant DNN models are memory efficient and hardware-friendly; on the hardware side, resistive random-access memory (ReRAM) based accelerators are promising for in-situ processing of DNNs. In this work, we design an accelerator named ReBoc for accelerating block-circulant DNNs in ReRAM to reap the benefits of light-weight models and efficient in-situ processing simultaneously. We propose a novel mapping scheme which utilizes Horizontal Weight Slicing and Intra-Crossbar Weight Duplication to map block-circulant DNN models onto ReRAM crossbars with significant improved crossbar utilization. Moreover, two specific techniques, namely Input Slice Reusing and Input Tile Sharing are introduced to take advantage of the circulant calculation feature in block- circulant DNNs to reduce data access and buffer size. In REBOC, a DNN model is executed within an intra-layer processing pipeline and achieves respectively 96× and 8.86× power efficiency improvement compared to the state-of-the-art FPGA and ASIC accelerators for block-circulant neural networks. Compared to ReRAM-based DNN accelerators, REBOC achieves averagely 4.1× speedup and 2.6× energy reduction.
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- PAR ID:
- 10179369
- Date Published:
- Journal Name:
- 2020 Design, Automation & Test in Europe Conference & Exhibition (DATE)
- Page Range / eLocation ID:
- 1472 to 1477
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.23919/DATE48585.2020.9116422
