Spread Spectrum Clocks have the following advantages:
1. Peak EMI reduction (from 6 to 18 dB-typ) on each harmonic.
2. Programmable EMI reduction and functions.
3. Frequency Syntheses (Multiplication) to eliminate higher order expensive and unstable crystals.
4. No degradation in rise and fall times.
5. Faster Time-to-Market: Reduced development time.
6. Reduced product development and manufacturing costs.
7. Reduction of PCB layers leading to additional product manufacturing costs reduction.
Check EMI Reduction Clocks Overview and Parametric Search for the devices at the following link: