Behavior Simulation of SSC Generator With Adjustable Modulation Frequency and Depth

In this paper, the spread spectrum clock (SSC) is primarily implemented by a digital phase interpolation circuit (PI) and a triangle modulation generator (TMG). The TMG is divided into an integer part and a fractional part implemented by delta-sigma modulation. As a result, the PI can achieve phase-compensated SSC generation. In this work, an SSC generator with switchable modulation frequencies of 100 kHz and 50 kHz and modulation depths of +/- 3% and +/- 1.5%, respectively, is presented.