UCC28065: Question about CS

David Kim2

Part Number: UCC28065

My board makes noise at input voltage 90Vac to 115Vac.
There is no noise above 115Vac.
The resistance of Rcs was changed from 300ohm to 2.7kohm, and it improved.

Is it okay to use the resistance of the Rcs as 2.7kohm?
I usually use a resistance in the 100 ohm range, but I'm worried that it's too big.
Please make sure you're all right.

Thanks

over 1 year ago

0 Ray DiCecco over 1 year ago

TI__Genius 10555 points

Hi David,

If the additional resistance improves your noise immunity, I would suggest that instead of increasing the resistor, go back to 100Ω but add a 33pF cap from CS to PGND.

Regards,

Ray

0 Ray DiCecco over 1 year ago in reply to Ray DiCecco

TI__Genius 10555 points

Hi David,

I have not heard back from you in a couple of weeks. For now, I will assume the addition of the cap from CS to GND solved your issue. If not, feel free to re-open the ticket.

Regards,

Ray

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UCC28065: Question about CS