Process to decrease the strength of an electric field produced by a high voltage conductive path of a printed circuit board and printed circuit assembly using same
A process to decrease the strength of an electric field produced by a high voltage conductive path on a printed circuit board and printed circuit assembly using same includes the steps of coating the upper side (5) of the conductive path or track (1) with a thick layer of electrically conductive coating material (4); and reflowing so that the upper edges (8, 9) of the track (1) are also covered with a relatively thick layer of coating material. The track (1) is thus embedded in a mass of coating material having more or less a rounded-shaped cross-section and the sharp upper edges (8, 9) of this track, where a strong electrical field is generally produced, are smoothed. As a result, the strength of the electrical field around the track (1) is reduced. In a preferred embodiment, a second track (13) similar to the first track (1) is created symmetrically thereto on the opposite surface (14) of the printed circuit board (3). This second track (13) is brought to the same potential as the first track (1) and is coated in a same way. Therefore, the electrical fields still produced at the lower edges (10, 11) of the track (1), which are not totally embedded in the mass of coating material because the latter do not adhere on the surface (2) of the printed circuit board (3), are counterbalanced by the electrical fields produced at corresponding opposite edges (15, 16) of the second track (13). The strength of the global electrical field around the tracks (1, 13) is thereby drastically reduced.
