Heat dissipation device for an electronic device

An electronic device (10) for a motor vehicle comprising:

• a tubular casing (12) formed of metal, said tubular casing extending longitudinally with openings at each of two ends (24, 26) of the tubular casing, the tubular casing (12) comprising a wall (31) having a curved profile comprising cooling fins (34) on an outer surface (32) of the tubular casing;
• an assembly of printed circuit boards (18) comprising a first plurality of printed circuit boards characterized as flexible, said first plurality of printed circuit boards comprising heat-generating electronic components (19), the printed circuit boards of the assembly being connected together by flexible conductive elements (92, 94);
• a first heat sink (14) arranged inside the tubular casing (12) comprising a curved wall (108) generally extending parallel to the wall (31) of the tubular casing (12);
• the first plurality of printed circuit boards being interposed between a curved inner surface (48) of the wall (31) of the casing (12) and the curved wall (108) of the first heat sink (14) so as to be able to dissipate the heat through the first heat sink (14) and through the curved wall (31) equipped with cooling fins (34) of the tubular casing (12);
• and
• the assembly of printed circuit boards (18) comprising a flat printed circuit board (82) distinct from the first plurality of printed circuit boards, a first face (138) of said flat printed circuit board (82) being arranged against a flat wall (114) of the first heat sink (14).