Table 9.
Experimental results for fully connected layer.
| Time | RISC-V | NPEs | Dmem | Total core | Energy per | |
|---|---|---|---|---|---|---|
| Experiment | (μS) | energy (nJ) | energy (nJ) | energy (nJ) | energy (nJ) | SOp (pJ) |
| [Baseline] | ||||||
| Graded spikes | 228 | 11.7 | 423.3 | 434.0 | 908.8 | 14.2 |
| Binary spikes | 179.9 | 8.4 | 288.7 | 525.8 | 853.1 | 13.3 |
| Spike-grouping | 121.8 | 13.4 | 291.8 | 155.0 | 481.9 | 7.5 |
| Binary Spike | ||||||
| +Quantization | 109.2 | 10.7 | 143.5 | 254.8 | 429.5 | 6.7 |
| Binary Spike | ||||||
| +Quantization | ||||||
| +Spike-grouping | 57.7 | 10.5 | 100.4 | 52.9 | 175.5 | 2.7 |
RISC-V energy includes RISC-V and its instruction memory. NPEs energy includes all NPEs, Loop buffer, and Event-generator blocks. Synaptic operation (SOp) energy is calculated by dividing the total core energy by 64 k (4,000 neurons, each processing 16 spikes).