SNVSC24 April 2021 LP8758-EA
Systems with periodic switching signals may generate a large amount of switching noise in a set of narrowband frequencies (the switching frequency and its harmonics). The usual solution to reduce noise coupling is to add EMI-filters and shields to the boards. The register-selectable spread-spectrum mode of the device minimizes the need for output filters, ferrite beads, or chokes. In spread-spectrum mode, the switching frequency varies randomly by ±5% about the center frequency, reducing the EMI emissions radiated by the converter and associated passive components and PCB traces (see Figure 7-3). This feature is enabled with the CONFIG.EN_SPREAD_SPEC bit, and it affects all the buck converter cores.