Sensitive electronic circuits need to be fully protected from extraneous electro–magnetic and radio frequency interference (EMI and RFI). This has typically been achieved by mounting metal shields or ‘cans’ directly to the PCB to fully shroud the required circuitry. These shields are often attached to the PCB using through–hole solder tails, manually soldered after the main assembly process. Not only is this time–consuming and costly but also, during initial setup and subsequent maintenance it is often necessary to access the circuitry and components under the shields. This requires de–soldering operations in often densely populated areas containing highly sensitive components. As a result there is a high risk of expensive damage occurring.
Harwin’s solution of using shield retaining clips, supplied in industry–standard Tape & Reel packaging, provide a automatic placement method which is soldered using standard SMT placement equipment. The shielding can is then fitted during final assembly within seconds. As it is possible to remove and refit the can a number of times, tuning and rework operations are simplified, and a minimal risk of damage is ensured. Therefore both initial production and rework costs are significantly reduced.
Harwin’s EMI/RFI clips are aimed at telecoms base stations, radio communications, data processing and in–car entertainment systems. Previous devices have been successfully used in diverse applications such as the Bowman Military radio project and automotive SatNav/DVD players.
New December 2015! Surface Mount EMI/RFI shield clips from Harwin are now available in 10 different sizes, to save PCB space and reduce assembly and rework time by eliminating through–hole manufacturing processes.
• Maxi clip – For shielding cans using 0.7–1.0mm thick material.
• Midi clips – For shielding cans 0.17–0.3mm thick.
• Mini clips – 40% smaller, for shielding cans 0.13–0.3mm thick.
• Micro clips – Low profile, for shielding cans 0.15–0.25mm thick.
• Corner clip – For securing 90 degree corners on cans 0.2–0.25mm thick.
See also EZ-Shield Cans