Frequently Asked Questions
This EMI Shielding FAQs page answers common questions about EMI shielding solutions, including CBS shields, Slot-Lok shielding, TechMesh products, ferrite cable solutions, and board-level shielding.
Whether you are designing for PCB applications, enclosures, or cable assemblies, these EMI Shielding FAQs provide helpful insights into materials, lead times, customization options, and performance considerations.
CBS Shields
What are typical lead times for CBS shields?
What materials are offered for CBS shields?
What retention mechanism is used for CBS shields?
CBS shields use retention fingers on the fences to hold covers in place. For added retention, dimples are available on the 40-CBS, 50-CBS, and 80-CBS series shields.
Are there any design limitations for CBS shields?
All CBS shields must have length and width in 1/4″ increments because of the pitch of the fingers on the fence.
Custom or modified CBS designs are very limited, so consider Slot-Lok shields for custom shielding applications.
Are CBS shields suitable for automated placement on a PCB?
Are there any NRE charges for CBS shield designs?
No
Slot-Lok
What are typical lead times for Slot-Lok shields?
Lead times vary based on shield complexity. As a general planning guideline, standard designs typically ship within 2 weeks ARO, while more complex designs usually require 3–4 weeks.
What materials are offered for Slot-Lok shields?
What retention mechanism is used for Slot-Lok shields?
Are there any design limitations for Slot-Lok shields?
Are Slot-Lok shields suitable for automated placement on a PCB?
Are there any NRE charges for Slot-Lok shield designs?
TechMesh Products
What are the typical lead times for TechMesh Products?
What unit of quantity the TechMesh Products come in, EA or FT?
Can TechMesh be customizable?
SMS
What are the typical lead times for SMS shields?
In Stock: Ships Next Day
Out of Stock: 1 week (or less) ARO to ship
What materials are offered for SMS shields?
Do the SMS shields come standard with ventilation holes?
SMS-1XX series: 1-piece shields with ventilation holes
SMS-3XX series: 1-piece shields without ventilation holes
SMS-2XX series: 2-piece shields (frame & cover) with ventilation holes on the cover
SMS-4XX series: 2-piece shields (frame & cover) without ventilation holes on the cover
Are the SMS shields suitable for automated placement on a PCB?
Can SMS shields be modified?
SMS shields are fully tooled standard shields & the designs are fixed. If modification is required, the part will be quoted as a new custom Slot-Lok design with any applicable NRE/tooling charges.
Beryllium Copper
What are the design limitations for Beryllium Copper Parts?
What are the lead times for Unplated and Plated BeCu Fingerstocks?
Tech Clips
What are typical lead times for Tech Clips & Mini Tech Clips?
In Stock: Ships Next Day
Out of Stock: 2-4 weeks ARO to ship
What is the shield material thickness that should be used with the Tech Clips & Mini Tech Clips?
Tech Clips: .008 – .010” shield thickness
Mini Tech Clips: .006 – .008” shield thickness
What is the minimum recommended shield undercover height that should be used with the Tech Clips & Mini Tech Clips?
Tech Clips: .147”
Mini Tech Clips: .061”
Are the Tech Clips & Mini Tech Clips suitable for automated placement on a PCB?
How many Tech Clips or Mini Tech Clips are needed to secure a shield in place?
The number of clips required varies by application and any special shock or vibration requirements, and must be tested individually. As a general rule of thumb, use at least one Tech Clip or Mini Tech Clip for every 0.75″ of shield side wall to ensure adequate cover retention.
For example:
A 1″ x 1″ shield requires 4 clips, with 1 clip on each side.
A 1″ x 1.5″ shield requires 6 clips, with 1 clip on two sides and 2 clips on the remaining two sides.
Will the gaps between clips affect the shielding effectiveness of the shield?
Shielding effectiveness depends on the targeted frequency range. At lower frequencies (<500 MHz), clips have negligible impact. At higher frequencies (>500 MHz), you need to place clips strategically to optimize shielding performance.
For high-frequency applications, add recesses on the bottom of the shield walls where they mate with the clips. This ensures the shield sits flush on the PCB around the perimeter, improving overall effectiveness.
Board Shields
Understanding Discoloration in Copper Alloys
The brownish-green residue that occasionally appears on copper alloys such as UNS C77000 (nickel silver) results naturally from oxidation. Known as patina, it forms when copper reacts with environmental factors including moisture, oxygen, acids, and sulfur compounds. Patina is typically harmless and often protects the metal by creating a barrier against further oxidation.
You can remove patina through cleaning and polishing if desired. This natural process develops more quickly in environments with high humidity or exposure to acidic substances. The brown-green coloration often enhances the aesthetic appeal of copper-based items. Importantly, patina does not indicate product defects; it highlights the natural properties of copper alloys.
For further information or specific inquiries, please feel free to contact us.
