A galvanically isolated DC-DC converter based on current-reuse hybrid-coupled oscillators

This brief presents a fully integrated dc-dc converter consisting of only two CMOS chips, which are a power oscillator with an integrated transformer and a full-bridge rectifier. A thick inter-metal oxide layer guarantees a galvanic isolation rating as high as 5 kV. A current-reuse hybrid-coupled oscillator is proposed, which is based on a three-winding tapped isolation transformer and improves both output power and silicon area occupation with respect to previous works. The converter is operated at 5-V power supply and is able to deliver up to 300-mW dc power at 10-V output voltage while exhibiting a power density and a power efficiency of 36 mW/mm2 and 24%, respectively.