UCC28070 variable output voltage

Chris Walters

Other Parts Discussed in Thread: UCC28070

I'm designing a PFC controller. I choose it because I'll need ~3.5kw output power and it supports running multiple controllers synchronized. I need my output voltage to be adjustable between 250-350volts, (120vac input). At first, I figured I could just adjust the feedback voltage divider to Vsense, but the datasheet mentions that the resistor divider network must be identical between Vsense and Vacin. So should I just vary Vsense, or both or is there a better way?

Thanks for any help...

over 14 years ago

0 Hong Huang over 14 years ago

TI__Guru 74075 points

To make flexible design such as in your intended applications, I would recommend digital control.

0 farhan alam12004 over 14 years ago in reply to Hong Huang

Prodigy 130 points

I am designing a 3.3Kw PFC circuit using ucc28070 .but i have problem with heating of the inductors.can i get any information or part number of inductor used in 5kW PFC reference design by TI.i have checked the Bill of materials that is on ti web but there is nothing about the inductor.

best regards

0 Mike O' over 14 years ago in reply to farhan alam12004

TI__Guru* 86286 points

You might want to contact someone from the power lab to see if they can get you that information. I don't think any of the engineers that have done the reference designs are supporting the E2E. I went to the power labs web site and did not see any information for contacts. You might want to forwarded this question to the product information center. They can track down the designer for you. http://www-k.ext.ti.com/sc/technical_support/product_information_centers.htm

The other option you have is to contact the magnetic manufactures like Cooper, Coil Craft, or Wurth to see if they can design something for you. Magnetics is not my specialty I usaly go to these manufactures for my magnetic designs.

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UCC28070 variable output voltage