Interference signal decoupling using a board-level EMI shield that adheres to and conforms with printed circuit board component and board surfaces

A decoupling circuit on a printed circuit board, comprising:

• an electrical filter circuit, electrically connected between an interconnect post and a ground land coupled to a ground plane, the filter configured to shunt conducted interfering signals received over the interconnect post to the ground plane, wherein components of the electrical filter circuit form a first receiver loop in which interfering signals can be induced;
• and
• a second receiver loop comprising a conductive coating of an electromagnetic interference (EMI)shield conformingly adhered to surfaces of the decoupling circuit, and a conductive path of the first receiver loop,
• wherein the second receiver loop is adapted to have induced therein a signal having a direction and magnitude sufficient to cancel interfering signals induced in the first receiver loop.

A printed circuit board comprising:

• a printed wiring board having a surface on which components are mounted;
• an interconnect post mounted in the printed wiring board;
• a ground plane within the printed wiring board;
• at least one ground land connected to the ground plane;
• an electrical filter circuit comprising one or more components mounted on the printed wiring board and electrically connected to the interconnect post and a first ground land;
• and
• a conformal electromagnetic interference (EMI) shield adhered to surfaces of the printed circuit board, comprising a dielectric coating directly contacting surfaces of the one or more electrical filter components and surface traces, and a conductive coating directly contacting and covering the dielectric coating and first ground land.

A decoupling circuit on a printed circuit board, comprising:

• an electrical filter means, electrically connected between an interconnect post and a ground land coupled to a ground plane, for shunting conducted interfering signals received over the interconnect post to the ground plane, wherein components of the electrical filter circuit form a first receiver loop means in which interfering signals can be induced;
• and
• a second receiver loop means for having induced therein a signal having a direction and magnitude sufficient to cancel interfering signals induced in the first receiver loop,
• wherein said first and second receiver loop means share a conductive path.