Abstract: A multiple output isolated DC-DC converter with coreless PCB transformer was proposed and demonstrated. The four consistent output voltages were achieved with two series coreless stacked PCB transformer. The cross coupled tank and coreless PCB transformer formed sustaining oscillation. The Schottky diodes were used as rectification devices. The design of the coreless PCB transformer and the overall circuit were implemented by simulation. Experimental results showed that the four output voltages were 14 V. The delivered power was 1.5 W at 45% efficiency.