26 February 2024 in IEEE Access
Neural network quantization represents weights and activations with few bits, greatly reducing the overhead of multiplications. However, due to the recursive accumulation operations, high-precision accumulators are still required in multiply-accumulate (MAC) units to avoid overflow, incurring significant computational overhead. This constraint limits the efficient deployment of quantized NNs on resource-constrained platforms. To address this problem, we present a novel framework named CANET, which adapts the 8-bit quantized model to execute MAC operations with 8-bit accumulators. CANET not only employs 8-bit carry-aware accumulators to represent overflow data correctly, but also adaptively learns the optimal format per layer to minimize truncation errors. Meanwhile, a weight-oriented reordering method is developed to reduce the transfer length of the carry. CANET is evaluated on three networks in the ImageNet classification task, where comparable performance with state-of-the-art methods is realized. Finally, we implement the proposed architecture on a custom hardware platform, demonstrating a reduction of 40% in power and 49% in area compared with the MAC unit with 32-bit accumulators.
4 May 2026 in IEEE Transactions on Very Large Scale Integration (VLSI) Systems
This brief presents a Booth-based all-digital SRAM compute-in-memory (CIM) macro designed for high-efficiency multiply-and-accumulate (MAC) operations in artificial intelligence applications. The architecture incorporates three key innovations: 1) a pre-encoding (PENC) scheme utilizing a Booth-based consolidated truth table, designed to reduce encoder complexity and computing unit overhead; 2) a minimalist bitwise processing technique, employing only two transistors for bit retention and shifting, aimed to minimize computational complexity within the subcomputing array; and 3) a multiphase product summation approach, integrating unified negative compensation with global sign bit expansion, intended to lower power consumption during partial product accumulation and final addition. The proposed architecture is readily adaptable to multiplications across diverse bit widths and accommodates flexible CIM array sizes, ensuring high scalability. Measurement results from a 55-nm-CMOS process demonstrate that the proposed CIM macro achieves an energy efficiency of 16.8 TOPS/W under 8b/8b MAC operations.
8 May 2026 in IEEE Transactions on Circuits and Systems I: Regular Papers
The energy efficiency of object detection processors based on traditional artificial neural networks (ANNs) is constrained by intensive multiply-accumulate operations and frequent memory accesses. Spiking neural networks (SNNs), characterized by biological plausibility, multiplier-free computation, and inherent sparsity, offer a promising alternative for energy-efficient inference. However, deploying SNNs for high-resolution object detection faces three key challenges: 1) long time-steps to maintain accuracy; 2) redundant weight access across time-steps; and 3) substantial external memory access (EMA) incurred by intermediate feature maps (FM). To address the above challenges, a dedicated SNN processor is presented with three contributions: 1) a customized short time-step quantized spiking YOLO (QS-YOLO) model, achieving 65.80-72.90% mAP on VOC2007 within only 1–4 time-steps through a progressive temporal compression (PTC) and quantization framework; 2) a novel weight-locally-distributed stationary spatio-temporal sequential interleaving (WLS-STS) dataflow, enabling single weight access across all time-steps while supporting flexible time-step configuration without loss of processing element (PE) utilization; and 3) a workload-aware dynamic global buffer allocation strategy to eliminate FM-EMA. The proposed processor incorporates a heterogeneous dual-core architecture, comprising a spike-driven accumulate unit (SAU) and a multiply–accumulate unit (MAU), to efficiently accelerate both spiking and non-spiking operators in QS-YOLO. Implemented on XCVU13P FPGA, the processor achieves a peak energy efficiency of 146.48 GOPS/W at 100MHz. Compared with existing object detection FPGA processors, the proposed processor achieves state-of-the-art energy efficiency.
15 April 2026 in SSRN Electronic Journal
Spiking Neural Networks (SNNs) have emerged as an essential paradigm for brain-inspired computing, achieving superior energy efficiency on neuromorphic hardware. However, as network scale increases, SNNs encounter growing challenges in deployment efficiency. While structured pruning provides a practical approach, existing methods typically rely on a dense-to-sparse training pattern, which incurs high memory overhead during training and fails to exploit the efficiency of sparse computation from the outset. There is a lack of effective frameworks that enforce structured sparsity within a sparse-to-sparse training regime for SNNs. To bridge this gap, we propose the Channel Dual-phase Sparsity (C-DPSS) framework. This approach leverages Dynamic Sparse Training (DST) to enable efficient topology exploration while progressively enforcing hardware-friendly structured sparsity. Our methodology is grounded in the empirical observation that channel-level neuronal activity patterns stabilize significantly earlier than synaptic weights during training. Motivated by this temporal discrepancy, C-DPSS employs a dual-phase saliency metric during training. It defines an early exploration phase dominated by neuronal dynamics, and smoothly transitions to a late refinement phase driven by synaptic efficacy. Extensive experiments on both static and neuromorphic benchmarks demonstrate that C-DPSS provides a robust accuracy-efficiency trade-off. Notably, for VGG-16 on CIFAR-10, our method achieves a 50% channel sparsity and a 42% decrease in Synaptic Operations (SOPs) with no accuracy loss, outperforming state-of-the-art static structured pruning methods. Furthermore, we validate the scalability of our approach by providing a feasibility demonstration of sparse-to-sparse structured pruning on the ImageNet-1K. Our code is available at: https://github.com/JunLi0514/C-DPSS.