Design of a digitally-controlled LLC resonant converter with synchronous rectification

In this paper, a digitally-controlled LLC resonant converter with synchronous rectification is developed. The advantages of the LLC resonant converter include ability to operate over a wide input voltage range and the fact that zero voltage switching (ZVS) is achievable over the entire operating condition. Moreover, synchronous rectifier reduces conduction loss in LLC resonant converter; hence increases the efficiency further. Using a digital controller to replace its analog counterpart boasts the advantages such as components reduction and more flexible design. Experimental results show that the measured conversion efficiencies of the designed digital LLC resonant converter are all higher than 92% under all output voltage and load conditions.