| 摘要 |
Transverse electromagnetic mode (TEM) radiation emitted from a side edge portion of a circuit board substrate portion during operation of the circuit board is intercepted by a specially designed shield structure carried by the substrate side edge portion, and the intercepted radiation is conductively returned to the substrate ground plane, through a relatively short grounding path, for return to the emitting source(s). In one form thereof, the shield is a copper plating material extending along and covering the substrate side edge portion and adjacent peripheral portions of the opposite sides of the substrate. In another form thereof, the shield is a snap-on metal shield structure that is removably mounted around the substrate side edge portion. The shield may be electrically coupled to the substrate ground plane by directly contacting a ground plane edge portion with the copper plating, using a filter structure to couple the shield to the ground plane, or otherwise using an external grounding path. When the shield is formed by using a copper plating, the shield may also be used as a grounding connection by sliding it into a metal chassis support rail structure. The grounding connection may be improved by covering opposites side portions of the copper plating shield with a masking material having spaced series of holes therein, and then filling the holes with a solder material that forms solder bumps projecting outwardly beyond the outer sides of the masking material.
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