This application note demonstrates the electromagnetic compatibility (EMC) benefits of internal, hot-loop multi-layer ceramic capacitors (MLCCs) in a step-down converter module. The MPQ4323M-AEC1 is a step-down converter module that can pass CISPR25 Class 5 with only three external EMC filter components. The results are compared with the MPQ4323C-AEC1, a step-down switching converter module that works with external hot-loop MLCCs. Advantages of the step-down converter module with MLCCs include improved EMC, reduced board space, and a shorter development time.