Combining diagonal connection and cancellation turn in electromagnetic interference filtering

In this study, a new printed circuit board (PCB) implementation of the diagonal connection is proposed. The two capacitors that are connected diagonally are laid out as close as possible and in such a way that their currents have opposite directions. The new layout combines the benefits of the so-called `cancellation turn´ with the benefits of the diagonal connection, without the need for additional PCB space and components. The experimental results show that the self-resonant frequency of the diagonally connected capacitors increased by 32%. Additionally, the coupling between the diagonally connected capacitors and a capacitor on the other side of the filter was reduced by 20-25 dB.