An improved dual voltage automotive electrical system in which low voltage loads are powered by a series resonant DC-DC converter operated at a fixed switching frequency below the resonant frequency of its tank circuit. With this arrangement, the converter provides a fixed conversion ratio from the regulated...http://www.google.de/patents/US6151222?utm_source=gb-gplus-sharePatent US6151222 - Dual voltage automotive electrical system with sub-resonant DC-DC converter
