UCC28950: Reosnant current in Primary side

Venkatesh B

Intellectual 783 points

Part Number: UCC28950
Other Parts Discussed in Thread: UCC28951

Hi ,

I am facing same issue of Ringing caused by secondary side Leakage Inductance and Parasitic capacitor

P=3300W,Vinput=380 to 420V DC,Output is 350V to 450V DC

I am planning to follow RCD snubber in Reference design UCC28950

How to calculate RCD Snubber values for my Voltage and current ratings, since UCC28950 only has 12V,50A

Kindly share me any calc tool or equation please

Thank you

venkatesh

over 1 year ago

0 Mike O' over 1 year ago

TI__Guru* 85926 points

Hello,

Your inquiry is under review and I will get back to shortly.

Regards,

0 Mike O' over 1 year ago in reply to Mike O'

TI__Guru* 85926 points

Hello,

The following thread will go into detail on how to setup an RCD clamp on the SRs of a phase shifted full bridge. Please note that the thread refers to the UCC28951. However, it will work with the UCC28950 as well.

https://e2e.ti.com/support/power-management-group/power-management/f/power-management-forum/1294915/ucc28951-design-1kw-supply-guide-step-1-using-transformer-gate-drive/4980493?tisearch=e2e-sitesearch&keymatch=ucc28951%25252520clamp#4980493

Regards,

0 Venkatesh B over 1 year ago in reply to Mike O'

Intellectual 783 points

Thank you mike

I will go through it,hope design rules are same for 400V secondary too

Thank you

venkatesh B

0 Mike O' over 1 year ago in reply to Venkatesh B

TI__Guru* 85926 points

Hello,

Thanks for letting me know.

Regards,

Power management

Power management forum

UCC28950: Reosnant current in Primary side