Apparatus and method for RF shielding of a printed circuit board

• US 6,180,876 B1
• Filed: 12/29/1997
• Issued: 01/30/2001
• Est. Priority Date: 12/29/1997
• Status: Expired due to Term

• Current Assignee: Blackberry Limited
• Original Assignee: Research In Motion Limited (Blackberry Limited)
• Inventors: Holmes, John A.
• Primary Examiner(s): Cuchlinski, Jr., William A.
• Assistant Examiner(s): MANCHO, RONNIE M
• Application Number:
  US08/999,354
• Time in Patent Office: 1,128 Days
• Field of Search: 174/35.GC, 174/35.MS, 277/233, 277/234, 277/901, 361/818, 361/814, 361/816
• US Class Current: 174/367
• CPC Class Codes: H05K 3/341 Surface mounted components
• CPC Class Codes: H05K 9/0032 having multiple parts, e.g. frames mating with lids
• CPC Class Codes: Y10S 277/902 Seal for sterling engine

Abstract

An apparatus and method for shielding discrete areas of a printed circuit board from electromagnetic interference includes a frame and separate shielding lids. The frame is surface mount soldered onto the solder tracks of a printed circuit board and provides fences which divide the printed circuit board into discrete areas. Separate shielding lids of different heights are provided to shield the separate discrete areas. The separate shielding lids mount inside the discrete areas defined by the fences of the frame and attach to lips formed on interior surfaces of the fences.

Claims

1. An electromagnetic shielding apparatus for a circuit board having solder traces comprising:

a) a lid for shielding a discrete area of the circuit board; and

b) a one piece frame unit configured for securement to the solder traces of the circuit board, said frame having continuously connecting fencing extending in an outward direction from the surface of the printed circuit board, said fencing being arranged to surround the discrete area, said fencing having separate interior surfaces each of which surrounds and defines the periphery of the discrete area, said interior surface being configured to retain said lid in the installed position to said fencing to encapsulate the discrete area.

2. The shielding apparatus according to claim 1 wherein the lid is retained by the interior surface in the installed position by an interlock mechanism.

3. The shielding apparatus according to claim 2 wherein the interlock mechanism comprises a lip on the upper section of the interior surface and at least one dimple on the lid walls for locking the lid into position by latching underneath said lip.

4. The shielding apparatus according to claim 1 wherein the lid includes a top section and lid walls that engage the edges of the top section, the apparatus also having at least a first and a second lid wherein the height of said lid walls of said first lid is different from the height of said lid walls to said second lid.

5. The shielding apparatus according to claim 1 wherein said fencing includes a section of fencing having opposite surfaces that are each interior surface for separate discrete areas.

6. The apparatus according to claim 1 further comprising a second lid for shielding a second discrete area and wherein said frame is also arranged to surround said second discrete area and said fencing has separate interior surfaces each of which surrounds and defines the periphery of the second discrete area.