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RDR-805.... component temperatures with and without the heat spreader?

Posted by: treez on Sun, 05/09/2021


Please could you give the component temperatures for RDR-805 for with and without the alu heat spreader?

(With PCB in enclosure in both cases)

Also, on page 93, i noticed the PFC inductor current is in DCM...i thought HiperPFS operated only in CCM?

Also, how much does the heat spreader have an effect on radiated EMC measurements? (The radiated EMC test for approvals)?

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Submitted by PI-Spark on Wed, 05/12/2021

Hi treez,

Thank you for using Power Integrations products.

You can check Section 14 for the RDR-805 component temperature

  • 14.1 - 14.2: Without heat spreader and without enclosure (25C ambient)
  • 14.3: With heat spreader and inside enclosure (45C ambient)

As you would expect, if the board is tested inside the enclose but without heat spreader, component temperature would be higher so a heat spreader is desirable.

The PFC stage using HiperPFS is typically designed to operate in CCM at the worst-case condition (e.g. 20V / 5A output, 90VAC input).

But it can also operate in DCM during lighter load conditions such as what you see in the report (15V / 5A output, 230VAC input).

RDR-805 document only shows Conducted EMI performance. We currently do not have radiated EMI data for RDR-805.