• State Resolved
  • Locked Locked
  • Replies 1 reply
  • Subscribers 63 subscribers
  • Views 270 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.

High current DC-DC converter

Tony Garvey
Prodigy 160 points
Other Parts Discussed in Thread: TPS40195

I am designing a high current dc-dc stage for a charging dock.  I have an external 19V brick psu.  My dock will cater for qty 5 x 5V 2A charging receptacles.  Am I best advised to use qty x1 dc dc converter giving 5V 10A output (based on TPS40195)?  Or might I be better off having 5 individual point of load converters each rated for 5V 2 A. 

Is it mainly a BoM cost decision?  Or are there other technical considerations which would favour one approach over the other?

  • 0
    TI__Guru 56825 points

    There are several techncial implications of this decision.

    With a single converter:

    All voltages will be the same

    A fault condition (such as a short on one output) will affect all outputs

    All outputs will power up together

    It will have a lower bom cost and generally higher efficiency when fully loaded

    Noise generated by a load on one output can affect all of the ouptuts

    With Independant Converters

    A fault candition may only affect the faulted output

    Outputs can be independantly enabled or sequenced

    Noise can isolated between loads.

    Another Alternative would be to use a single 10A 6V converter with seperate 2A 5V load switches to allow the 5 outputs to be fault protected and enabled by the load switches with a lower bom cost than 5 seperate 2A converters.  If your system allows the charging regulars to be enabled/disabled independantly or, if possible, by auto-detecting the presence of a load, 5 seperate converts could be much more efficient when only a few loads are present.