more than you expect Power Sup- Topology Schematic Power (Watts) Typical Efficiency Relative Cost Magnetics Required DC Transfer Function (Vout/Vin) Maximum Universal Multiple Practical Input Outputs Duty Cycle (90-264) VAC Vout<Vin Range Vout>Vin Range __________ Flyback Isolated Topologies Forward Push-Pull Non-Isolated Topologies HalfBridge 150 150 500 500 75 75 80 85 √ 2xPoutxLPrixFreq ___________ Vin 0.9 Yes Yes Yes Yes 1.8 Transformer and Inductor 2Ns ___ xD Np 0.45 Yes Yes Yes Yes 1.8 Transformer and Inductor Ns ___ xD Np 0.45 No Yes Yes Yes 2 Transformer and Inductor Ns ___ xD Np 0.45 Yes Yes Yes Yes Frequency Dependent Based on Resonant Tank Transfer Function 0.45 Yes Yes Yes Yes 1.5 Transformer Resonant LLC 500 90 2 Buck 500 85 1 Single Inductor D 0.9 No No Yes No Boost 150 70 1 Single Inductor 1 _____ 1–D 0.9 No No No Yes BuckBoost 150 70 1 Single Inductor –D _____ 1–D 0.9 No No Yes Yes 1.2 Coupled or Two Inductors D _____ 1–D 0.9 No No Yes Yes 1.2 Coupled or Two Inductors –D _____ 1–D 0.9 No No Yes Yes Sepic Ćuk www.we-online.com/midcom 150 150 75 75 Transformer INSIGHT DESIGN 9997067 • APRIL 2013 Switch Mode Power Supply Topologies Compared