UCC256301: How to calculate compensation of TLV431 for 40V,3A application

Shaquille Chen

Intellectual 1770 points

Part Number: UCC256301

Dear Team,

I am working on PFC+ LLC for 40V,3A application for TV application.

The load regulation are pretty worse if I use EVM default compensation setting.

The output are 41V at no load but 40V at 3A load.

Adjust the compensation can reduce the voltage different between different load.

How to optimize the compensation here? Is there any technique document about compensation of UCC25630x?

Thanks

Shaq

over 7 years ago

0 Benjamin Lough over 7 years ago

TI__Mastermind 27135 points

Hi Shaquille,

Thanks for your interest in UCC256301. We do have one application note available for LLC converter compensation. Please note this is not specific for UCC256301 however:www.ti.com/.../slua582a.pdf.

Did you measure the loop response of the converter? If yes, could you share with me? May I see your schematic?

Best Regards,
Ben Lough

0 Benjamin Lough over 7 years ago in reply to Benjamin Lough

TI__Mastermind 27135 points

Hi Shaquille,

To follow-up, take a look at the voltage on the FB pin. If it is not close to 7V, you may need more gain in your compensation. Are you able to share schematic with me? Have you measured the loop response of the converter?

Best Regards,
Ben Lough

0 Benjamin Lough over 7 years ago in reply to Benjamin Lough

TI__Mastermind 27135 points

Hi Shaquille,

As it has been almost two weeks since your original post without any follow up response from you, I will go ahead and close this thread. If you need further assistance with this design, please begin a new post.

Best Regards,
Ben Lough

Power management

Power management forum

UCC256301: How to calculate compensation of TLV431 for 40V,3A application