In the Switch Mode topology there is typically a PFC choke, a diff mode choke, a switching transformer and an output choke. The PFC choke maintains the voltage/current phase relationship with the goal of minimizing power loss from the input voltage (typically AC). The diff mode choke’s function is to reduce noise in the system. Efficiency and stability is a function of the switching transformer and the key consideration is consistent performance across the required range of frequencies. The output choke acts as a storage element and as a filter. Optimal design within the topology is best achieved utilizing a systems design approach to the magnetics subsystem, incorporating all of the fore mentioned devices.