Design Considerations in the Use of Board Level Shields

In today’s electronic devices, increasing use of board level shields is appearing, especially in small, portable hand-held devices such as cell phones and PDAs. Board level shields are essentially a metal cover for EMI containment that is placed over a noisy circuit or device and soldered directly onto the printed circuit board. This hopefully eliminates or reduces the amount of shielding from the outer enclosure or case required by the board.