by Gheorghe Plasoianu @ edn.com
Many applications require positive and negative supply voltages, with only one voltage requiring tight regulation. This Design Idea describes a dual-output, hybrid SEPIC–Ćuk converter whose positive output voltage can be lesser or greater than the input voltage. The unregulated negative output is a mirrored replica of the positive output.
SEPIC/Ćuk converter sprouts second output – [Link]