UCC28730-Q1: Flyback Controller with PSR

Hi Asha

Thank you for reaching out.

Yes, UCC28730 should work for this application.

Shown below are some designs but some values needs to be changed for getting 28V output.

https://www.ti.com/reference-designs/index.html#search?keyword=UCC28730

Regards,

Harish

Hello Harish,

Also i see UCC28700-Q1 suiting my application , how do we compare and decide which is the best option.

To highlight one of the difference , HV pin is not available in 700 , it uses a Rstart resistor for initial start up!

Hi Asha,

You can use UCC28700 also. This does not have integrated HV startup. So if standby power is a major concern UCC28730 might be better.

Regards,

Harish

I see another IC UCC24650 used for secondary side control since it is PSR device. Using of UCC24650 is it mandatory?

Or can we go with UCC28730 alone. Please provide your view!

In the UCC28730 design calculator under technical documentation, is it considered for a single phase AC Input?

Because under recommended minimum voltage on input bulk capacitors, my equivalent DC Voltage is not matching for the input AC.

Could you provide your feedback!

Hi Asha,

You need to scale the AC values to equivalent DC values by factor of 1.414 in the excel calculator tool.

UCC24650 is used for minimizing the o/p cap requirement when load transient is applied from no to full load. This can help cut down cap requirement by 1/7 reducing size on board.

Regards,

Harish

Since the excel sheet is protected , how do i edit the same for my three phase input. 

Thank you!

Will get back to you for technical queries.