Low-cost energy-efficient SMPS delivers up to 90 W peak from an EE-25 core transformer

An SMPS that delivers peak power of up to 3× its rated full load power without requiring an over-sized power transformer is proposed. The operation of the control scheme used to achieve the high peak power capability and very consistent efficiency versus load is described. The low parts count implementation of required output protection functions is also explained. Finally, experimental evaluation results obtained from a prototype of a universal input, single output (30 V at 1.07 A), flyback, ac-dc converter are presented.