摘要 |
The present invention relates to grounding a shielding device comprising a conductive housing metal box for a filter, particularly when the filter is mounted on a circuit board using surface mounting technique. As taught by the invention, protrusions (5) have been formed on a wall (4) of the conductive housing (1) of the box on which the box is grounded primarily by means of a soldering connection. The protrusions (5) can be so formed that they define as accurately as possible the level (A-A) in order to achieve good and uniform grounding in the surface mounting. With the design of the invention, +/- 0.05 mm planarity requirement can be met. In a primary embodiment, the wall of the shell (1) is of silver-coated aluminium, the thickness thereof being of the order 0.3 mm. The bumps are formed by embossing, the nominal height thereof being 0.3 mm. <IMAGE> |