LSFQ: A Low-Bit Full Integer Quantization for High-Performance FPGA-Based CNN Acceleration

The effective implementation of quantization depends not only on the specific task but also on the hardware resources. This article presents a hardware-aware customized quantization method for convolutional neural networks. We propose a learnable parameter soft clipping full integer quantization (LSFQ), which includes weight and activation quantization with the learnable clipping parameters. Moreover, the LSFQ accelerator architecture is customized on the field-programmable gate array (FPGA) platform to verify the hardware awareness of our method, in which DSP48E2 is designed to realize the parallel computation of six low-bit integer multiplications. The results showed that the accuracy loss of LSFQ is less than 1% compared with the full-precision models including VGG7, mobile-net v2 in CIFAR10, and CIFAR100. An LSFQ accelerator was demonstrated at the 57th IEEE/ACM Design Automation Conference System Design Contest (DAC-SDC) and won the championship at the FPGA track.