Proper control loop phase and gain measurements should be made by factory experts possessing (expensive) equipment and commensurate experience. For those who do not have access to one or either of these, there is an alternative.
One potential source of emissions is the switching node, referred to as SW on many schematics. The SW node copper can act as an antenna, transmitting the noise generated by fast and efficient high power switching events. This is the main source of emissions for most switching regulators.
Automotive application circuits must meet strict EMI standards to avoid interfering with broadcast and mobile service frequency bands. In this article we look specifically at two possible solutions for a 4-switch buck-boost controller and compare EMI chamber results.
A Practical Method for Separating Common-Mode and Differential-Mode Emissions in Conducted Emissions Testing - BlogAugust 09, 2021
EMI from switching regulators is broken down into radiated and conducted emissions (CE). This article focuses on conducted emissions, which can be further classified into two categories: common-mode (CM) noise and differential-mode (DM) noise. Why the CM-DM distinction?