Glossaire: Resonance converter
Resonant converters are variants of basic circuits which reduce switching losses by taking advantage of resonance effects. Resonant converters achieve the very highest efficiencies and often work with very high switching frequencies. The half-bridge resonant converter is in widespread use.
Due to the nature of the system, resonant converters are very difficult to control, so that power supplies which use a resonant converter are usually built-up in several stages. A switching regulator conditions the input voltage for the resonant converter which then takes over the role of energy transfer, galvanic isolation and voltage matching.