TVS for EMI Filtering

TVS for EMI Filtering



Design Notes:

Protection Application:
SMPS designs often employ large and expensive electrolytic filter capacitors. These are very sensitive to overvoltage events and can fail catastrophically with a loud explosion. To prevent this, designers often call for high voltage ratings on these capacitors.
Solution Description:
TVS diodes provide such precision clamping voltages that designers can often use lower voltage-rated capacitors. The capacitor cost savings is often sufficient to pay for the TVS diode and still provide a cost reduction on a more robust design. The TVS voltage should be carefully selected to be above the maximum line voltage but below the rated voltage of the capacitor. With an MOV at the input, most designs can use an SMBJ350CA device.
Companion Solutions:
Through-hole P6KE350CA TVS Diodes may also be used.
Regulatory Issues:
Standards will vary depending on the product to be protected. Examples include: IEC 61000-4-5 UL 1950 IEC 950
Unique Features:
Does not apply.
Application Warnings:
Does not apply.

Solutions

Solutions