TIS EMI shield can replace Sil-pad shield 09SPS01-002 (Heatsink Insulator from Bergquist Company Sil-PadShield400,TO-220)

features and Benefits

• Bonded laminate

• Electrically isolating

• Copper shield between layers of Sil-Pad

• Pre-tinned 60/40 solder point for easy grounding

Sil-Pad Shield is a laminate of copper with Sil-Pad thermally conductive insulators. Sil-Pad Shield provides:

• Shielding effectiveness of 50dB or higher  

• Good thermal transfer

• Reduced labor costs due to the elimination of having to apply thermal grease

Problem:
Radio Frequency Interference (RFI) is produced by heat sink current. The capacitance between a TO-3 encapsulated transistor and its heat sink is typically 100pf when a mica or other insulating washer is used. A power supply constructed with a standard insulator and a grounded heat sink can be expected to produce about 10 times more interference than is permitted.

Solution:
1. The use of chokes, filters and LC networks which have to be designed into the circuitry.

OR

2. Constructing a shield between the transistor and its heat sink by replacing the mica insulator with a Sil-Pad Shield (see illustration).

Typical Applications Include

• Switch mode power supplies

• EMI / RFI shield between PCB’s

Configurations Available

Sil-Pad Shield is available in many custom configurations to meet special requirements. Tooling charges vary depending on tolerances and complexity of the part.

Sil-Pad Shield is a laminate of copper with Sil-Pad thermally conductive insulators.Sil-Pad Shield provides:

• Shielding effectiveness of 50dB or higher

• Good thermal transfer

• Reduced labor costs due to the elimination of having to applyl thermal grease