Domain-Specific Accelerators
A Dataflow architecture design (AI Processor)
Summary:
A scalable deep-learning accelerator supporting the training process is implemented for device personalization of deep convolutional neural networks (CNNs). It consists of three processor cores operating with distinct energy-efficient dataflow for different types of computation in CNN training. A disparate dataflow architecture is implemented for the weight gradient computation to enhance PE utilization while maximally reuse the input data.
Reference:
Seungkyu Choi, Jaehyeong Sim, Myeonggu Kang, Yeongjae Choi, Hyeonuk Kim, and Lee-Sup Kim, "An Energy-Efficient Deep Convolutional Neural Network Training Accelerator for In Situ Personalization on Smart Devices," IEEE Journal of Solid-State Circuits, Oct. 2020.
Mixed-precision Processing units
Summary:
From two perspectives: 1) separate precision decision for each input data, 2) maintenance of high performance on inference, we configure the data with low-bit fixed-point of activation/weight and floating-point based error gradient securing up to half-precision. A novel MAC architecture is designed to compute low- and high-precision modes for the different input combinations. By substituting a high-cost floating-point based addition to brick-level separate accumulations, we realize both area-efficient architecture and high throughput for low-precision computation.
Reference:
Seungkyu Choi, Jaekang Shin, and Lee-Sup Kim, "A Deep Neural Network Training Architecture with Inference-aware Heterogeneous Data-type," IEEE Transactions on Computers, May 2022.
sparsity-aware PE architecture
Summary:
- Multi-window dataflow architecture for selective weight update
- Redundancy Censoring Unit (RCU)-based PE architecture
Reference:
- Jaekang Shin, Seungkyu Choi, Yeongjae Choi, and Lee-Sup Kim, "A Pragmatic Approach to On-device Incremental Learning System with Selective Weight Updates," ACM/IEEE Design Automation Conference (DAC), 2020.
- Kangkyu Park, Seungkyu Choi, Yeongjae Choi, and Lee-Sup Kim, "Rare Computing: Removing Redundant Multiplications from Sparse and Repetitive Data in Deep Neural Networks," IEEE Transactions on Computers, Apr. 2022.
High-performance DSP engine Implementation
Summary:
- A configurable baseband processing architecture that efficiently handles parallel sample streams targeting ultra-wide bandwidth inter-satellite optical communications for the target data rates exceeding 100 Gbps
- A parallelogram-style systolic accelerator, specifically designed for parallel processing for correlation kernels
Reference:
- Seungkyu Choi, Huanshihong Deng, Kuan-Yu Chen, Yufan Yue, David Blaauw, and Hun-Seok Kim, "ParaBase: A Configurable Parallel Baseband Processor for Ultra-High-Speed Inter-Satellite Optical Communications," ACM/IEEE International Symposium on Low Power Electronics and Design (ISLPED), 2024.