A printed circuit board comprises N power switching cells operating in parallel and respectively comprising a transistor leg, at least one decoupling capacitor and a gate driver circuit. Each transistor leg comprises respective first and second transistors in series, a drain of the first transistor being connected to a positive DC line, a source of the second transistor being connected to a negative DC line, a source of the first transistor being connected to a drain of the second through a connection middle-point connected to an output terminal. Each gate driver circuit controls respective switching ON and OFF of the corresponding first and second transistors. The N transistor legs of the corresponding N power switching cells are positioned to substantially form a convex polygon having N edges of substantially the same length, each one of the N transistor legs being positioned along one of the edges of the convex polygon.