UCC28720: Is there a component like the UCC28720 that can handle multiple output flyback?

Thomas Kofoed-Hansen

Prodigy 100 points

Part Number: UCC28720
Other Parts Discussed in Thread: UCC28730, UCC28C53

Tool/software:

I'm trying to find a, preferably PSR, flyback converter that can handle

input from 15Vdc to 150Vdc

2 individually isolated outputs

and has a very low no-load consumption. I started looking at the UCC28730 which at first glance looks perfect but can not handle the low input voltage. Then I looked at the UCC28720 but from the forum I can understand that this is not suitable for multiple output flyback.

Does anyone have a suggestion to what is best to use?

3 months ago

0 Hong Huang 3 months ago

TI__Guru 61865 points

Hi,

They can be used for two individual isolated outputs. But not in your case, since both ICs cannot start at 15V.

You can consider using UCC28C53.

0 Thomas Kofoed-Hansen 3 months ago in reply to Hong Huang

Prodigy 100 points

Problem is achieving low enough no-load consumption (< 20mW) with the UCC28C53, or have I gotten that wrong?

The datasheet states that the Ivdd = 1,3 -2mA and does not say anything about no-load or wait state current.

But for the UCC28720 it looks better. On the UCC28720 webpage there is a link to a document "Designing multiple output converters with primary side sensing" which kind of suggests that this can be used for multiple output fly-back.

I will talk to customer and challenge them about the minimum input voltage to see if he will raise it to 23V.

0 Hong Huang 3 months ago in reply to Thomas Kofoed-Hansen

TI__Guru 61865 points

Hi,

The ic is ok to use if the voltage can make it start up.

Power management

Power management forum

UCC28720: Is there a component like the UCC28720 that can handle multiple output flyback?