• State TI Thinks Resolved
  • Locked Locked
  • Replies 2 replies
  • Answers 1 answer
  • Subscribers 63 subscribers
  • Views 146 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

UCC28950: UCC28950

Stuart Linzer
Prodigy 30 points
Part Number: UCC28950

Tool/software:

Hi Support,  

Working on a phase shifted full bridge.  Converter Compensation Made Easy appnote mentions a second pole related to the output inductance and modulator gain on page 13.  For a phase shifted full bridge with current doubler secondary please help define the parameters and equation for the second pole.  

Datasheet for UCC28950 also mentions high frequency double pole at fsw/2 on page 57.  How does this relate to the modulator pole.  

Thank you,

Stuart Linzer

  • 0
    TI__Guru* 85616 points

    Hello,

    Your inquiry has been received and is under review.

    Regards,

  • 0 in reply to Mike O'
    TI__Guru* 85616 points

    Hello,

    This is peak current mode control the double pole should occur at fs/2.

    The compensation of the data sheet was taken from application note slua560 that you can find in the following link.  It goes through the step by step design process of phase shifted full bridge using the UCC28950.  There is even a section on how to compensate the voltage loop.  Within the application note there is a link to an excel tool that uses the same equations as the application note.  The excel file will even generate a loop gain bode plot so you can check your phase margin and gain margin.

    https://www.ti.com/lit/pdf/slua560

    Please note that the loop compensation in based on theoretical compensation and needs to be verified with large signal transient testing and a network analyzer.

    Regards,