2.4.1. 采样时钟频率
要达到建议的采样时钟频率,请按照以下步骤操作:
- SYNC_MODE和SAMPLE_SIZE参数决定采样时钟因素,然后用于确定需要的PLL设置。使用表 15来确定您配置需要的采样时钟因素。
- 使用前一步骤中确定的采样时钟因素决定PLL设置。表 16列出了 Stratix® V PLL Intel® FPGA IP的设置。
SYNC_MODE | 基准时钟频率 (MHz) |
采样时钟因素 | ||
---|---|---|---|---|
SAMPLE_SIZE = 64 | SAMPLE_SIZE = 128 | SAMPLE_SIZE = 256 | ||
0, 1 | 125 | 16/63 | 32/33 | 64/63 |
156.25 | 64/315 | 128/155 | 256/375 | |
2 | 主/从频率 | 64/63 | 128/153 | 256/375 |
3, 4 | 156.25 | 64/63 | 128/153 | 256/375 |
312.5 | 32/33 | 64/63 | 128/153 | |
5, 6 | 125 | 32/63 | 64/63 | 128/63 |
312.5 | 64/315 | 128/155 | 256/375 | |
7, 8 | 125 | — | — | 32/13 |
390.625 | — | — | 256/375 | |
9, 10 | 156.25 | 32/33 | 4/31 | 128/63 |
390.625 | 64/155 | 128/185 | 256/375 | |
11, 12 | 312.5 | 16/15 | 32/33 | 64/63 |
390.625 | 64/75 | 128/185 | 256/253 | |
13 | 62.5 | 64/63 | 128/153 | 256/253 |
125 | 32/33 | 64/63 | 128/153 | |
14 | 62.5 | 32/33 | 64/63 | 128/153 |
156.25 | 64/155 | 128/155 | 256/375 | |
15 | 62.5 | 64/63 | 128/153 | 256/253 |
312.5 | 64/155 | 128/155 | 256/375 |
采样时钟因素 | PLL计数器 | ||
---|---|---|---|
M | N | C | |
16/15 | 16 | 5 | 3 |
16/63 | 16 | 3 | 21 |
32/13 | 32 | 13 | 1 |
32/33 | 32 | 3 | 11 |
32 | 11 | 3 | |
32/63 | 32 | 3 | 21 |
64/31 | 64 | 31 | 1 |
64/63 | 64 | 9 | 7 |
64 | 21 | 3 | |
64/75 | 64 | 25 | 3 |
64/155 | 64 | 31 | 5 |
64/315 | 64 | 21 | 15 |
128/63 | 128 | 21 | 3 |
128/153 | 128 | 51 | 3 |
128 | 7 | 9 | |
128 | 9 | 17 | |
128/155 | 128 | 31 | 5 |
128/185 | 128 | 37 | 5 |
256/253 | 256 | 11 | 23 |
256/375 | 256 | 75 | 5 |
256 | 25 | 15 |