Spread spectrum clock generator: A low-cost EMI solution

In this chapter, spread spectrum clock generation (SSCG)-an advanced clock generation solution for electromagnetic interference (EMI) -is presented. EMI becomes critical as the clock speed and the degree of integration are increased. Various EMI suppression techniques are introduced in this chapter. Among EMI suppression techniques, SSCG is a simple but cost-effective solution since it requires no external components and can be implemented using existing clock generators. Several SSCG design approaches are described. Similar to other clock generators, SSCG also faces implementation issues, for example, noise, non linearity, and mismatch. Finally, recent spread spectrum clocking (S SC) modulation profiles are presented and discussed because the SSC modulation profile dominates the EMI performance.