Table 1. Spread-Spectrum Frequencies and Spread
| SS_MODE |
Allowed Frequencies |
CLKFBOUT_MULT_F |
DIVCLK_DIVIDE |
Spread |
| CENTER_HIGH |
100 MHz < Fin < 135 MHz |
28 |
1 |
± 1.82% |
| 135 MHz < Fin <185 MHz |
21 |
1 |
± 2.44% |
| 22 |
1 |
± 2.32% |
| 185 MHz < Fin < 275 MHz |
28 |
2 |
± 1.82% |
| 275 MHz < Fin < 350
MHz |
21 |
2 |
± 2.44% |
| 22 |
2 |
± 2.32% |
| 350 MHz < Fin < 550 MHz |
21 |
3 |
± 2.44% |
| 22 |
3 |
± 2.32% |
| CENTER_LOW |
100 MHz < Fin < 135 MHz |
56 |
2 |
± 0.90% |
| 135 MHz < Fin < 185
MHz |
42 |
2 |
± 1.20% |
| 44 |
2 |
± 1.15% |
| 185 MHz < Fin < 275 MHz |
56 |
4 |
± 0.90% |
| 275 MHz < Fin < 350
MHz |
42 |
4 |
± 1.20% |
| 44 |
4 |
± 1.15% |
| 350 MHz < Fin < 550
MHz |
42 |
6 |
± 1.20% |
| 44 |
6 |
± 1.15% |
| DOWN_HIGH |
100 MHz < Fin < 135 MHz |
28 |
1 |
– 1.82% |
| 135 MHz < Fin <185
MHz |
21 |
1 |
– 2.44% |
| 22 |
1 |
– 2.32% |
| 185 MHz < Fin < 275 MHz |
28 |
2 |
– 1.82% |
| 275 MHz < Fin < 350
MHz |
21 |
2 |
– 2.44% |
| 22 |
2 |
– 2.32% |
| 350 MHz < Fin < 550
MHz |
21 |
3 |
– 2.44% |
| 22 |
3 |
– 2.32% |
| DOWN_LOW |
100 MHz < Fin < 135 MHz |
56 |
2 |
– 0.90% |
| 135 MHz < Fin < 185
MHz |
42 |
2 |
– 1.20% |
| 44 |
2 |
– 1.15% |
| 185 MHz < Fin < 275 MHz |
56 |
4 |
– 0.90% |
| 275 MHz < Fin < 350
MHz |
42 |
4 |
– 1.20% |
| 44 |
4 |
– 1.15% |
| 350 MHz < Fin < 550
MHz |
42 |
6 |
– 1.20% |
| 44 |
6 |
– 1.15% |