• State TI Thinks Resolved
  • Locked Locked
  • Replies 3 replies
  • Answers 2 answers
  • Subscribers 63 subscribers
  • Views 283 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.

UCC28600: Reference Schematic Question

Michael Black2
Intellectual 350 points
Part Number: UCC28600

Hello,

I am using the UCC28600 to design a power supply with a 19V, 5A output. I came across the PMP5029 reference design which features a 19V, 2.2A output.

First Question: Is the PMP5029 capable of outputting 5A?

Second Question: What controls the output current capabilities of a flyback converter? is it just based on the input voltage and the switching frequency of the flyback controller?

Attached is the PMP5029 schematic for reference/

slur385.pdf

  • 0
    TI__Guru* 85806 points

    Hello,

    I don't believe the UCC28600 is capable of handling 5A.  However, to get more power out of it you would have to redesign the transformer for more storage energy by increasing the primary magnetizing inductance.  You can either use the excel design tool or webench to calculate the primary magnetizing inductance. 

    You would have to increase your input and output capacitor bank by a factor of 5/2 and adjust the current sense resistor.  This can be also verified and calculated with the webench tool or excel design tool.

    Regards,

     

  • 0 in reply to Mike O'
    Intellectual 350 points

    Ok, thank you. That is the conclusion I came to as well. I am a little confused when you say "I don't believe the UCC28600 is capable of handling 5A". I thought all that mattered was the amount of energy stored in the core? Doesn't the UCC28600 just try to maintain a certain voltage drop across the load?

    Edit: What section of the datasheet has the maximum Current, Voltage, Power ratings of a particular controller?

    Edit 2: There are some graphs on the UCC28600 that have data at > 5A such as efficiency vs output load, voltage vs current.

  • 0 in reply to Michael Black2
    TI__Guru* 85806 points

    Hello.

    The UCC28600 can be designed for applications up to 250 W.  The reference design PMP5029 cannot handle 5A as is.

    Regards,