Characterization of coreless printed circuit board (PCB) transformers

In this paper, coreless printed-circuit-board transformers are characterized. A range of coreless PCB transformers with different geometric parameters have been fabricated and tested. Based on a recently reported analytic method, the self inductances of these transformers are calculated. This analytical method is also extended to cover the prediction of the transformers' mutual inductance. All calculated parameters have been confirmed with measurements for the frequency range from 100 kHz to 30 MHz. These results provide useful information for the optimal design of coreless PCB transformers.