• State TI Thinks Resolved
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 63 subscribers
  • Views 43 views
  • Users 0 members are here
Support feedback
Options
Options
Related

UCG28826: valley switching under burst mode

Charles Zhang1
Expert 3430 points
Part Number: UCG28826

Tool/software:

Hi Team,

Per datasheet's description - "The UCG2882x's burst mode offers three 1st valley QR switching cycles followed by a minimum 70μs delay before the start of next burst packet."

However, the 2nd or 3rd valley can also be observed in the real bench test, or even on our EVM.

Is there any misunderstanding on the datasheet's description? Or do we need to modify the wording in the datasheet?

BR,

Charles 

  • 0
    TI__Prodigy 30 points

    Hi Charles,

    The UCG2882x goes to higher valley in burst mode only when the switching frequency hits the clamp of 250 kHz. This can happen at higher input and output voltages.

    The converter stays in 1st valley operation below 250 kHz of switching frequency. The converter switches to higher valley to limit the switching frequency below the burst mode clamp frequency of 250 kHz.

    Therefore, the burst mode description in the datasheet is correct. To avoid confusion, another sentence could be added to describe the operation after hitting the clamp frequency limit.

    Thanks,

    Somnath