A 40 TOPS Single-Chip Accelerator Enabling Low-Latency Inference for Deep Neural Networks

To achieve low latency for edge applications, a single-chip sparse accelerator is proposed, which can conduct deep neural network (DNN) inference only using limited on-chip memory. Private memory is eliminated, and all memories are shared to reduce power and chip area. An adaptive and variable-length compression algorithm is proposed to store sparse DNNs. A weak-constrained pruning algorithm is proposed to resolve load balance issue in kernel level, which can achieve almost the same sparsity as unconstrained pruning schemes (UCP). Based on these works, a low latency inference accelerator is fabricated in 28-nm CMOS with 8256 MACs and 9.4 MB on-chip SRAM, which can achieve a latency of 0.44 ms for YOLO3 tiny. For high-sparsity layers, our chip can achieve 6.1x speedup and a throughput of 40 TOPS. With a pruned YOLO model, our accelerator achieves 6.7x lower latency and 21.7x better energy efficiency than Jetson Orin. A high-speed evaluation platform is built to demonstrate real-time object detection at a throughput of 600 frames per second (fps) with a power of 1.34 W.