• State Resolved
  • Locked Locked
  • Replies 5 replies
  • Subscribers 63 subscribers
  • Views 376 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.

TPS2372-4EVM-006: Bulk capacitor

Daniel Campano
Intellectual 470 points
Part Number: TPS2372-4EVM-006
Other Parts Discussed in Thread: TIDA-050023

Hi All,

I'm developing a board based on the circuit reference of TPS2372-4EVM-006 and the bulk capacitor of 100uf doesn't fit at all in the board. I can't even fit 2 of 47uF in parallel, the best I can do is to fit just one capacitor of 47uf. Is it very important to fit a capacitor of 100uf?.

Regards,

Winsu

  • 0
    TI__Genius 9230 points
    Hi Winsu,

    The 100uF input bulk cap size is typical of converters that are in the 50W-70W range (class 6-8). 47uF would typically be seen in the 25W range. If you are planning on implementing TPS2372-4 with a converter in that range, I suggest testing with 100uF.

    Thanks,
    Tom Amlee
    PoE PD Apps Engineer
  • 0 in reply to Thomas Amlee
    Intellectual 470 points
    I'm planning to implement a TPS2372-4 set to Class 6 and the application will take 42w max. 47uf could do the job?
  • 0 in reply to Daniel Campano
    Intellectual 470 points

    Hi Tom,

    The problem is that I can't fit a 100uf capacitor as it is too high and it occupies a lot of space on the board, unfortunately that option for me is not possible. 

    What implications  I could have if I just fit a capacitor of 47uf ?. Could the PD have problems to finish inrush period and stablish steady voltage with just one capacitor of 47uf?, or the implications would just affect to the performance of the application if any?.

    Could two capacitors in parallel of 47uf improve the situation?, Could I find any problem for detection, classification and inrush period if I use two capacitors of 47uF in parallel instead of just one capacitor?.

    Thanks,

    Winsu

  • 0 in reply to Daniel Campano
    TI__Genius 9230 points
    Hi Winsu,

    For class 6 (50W), you should be fine with 47uF. On TIDA-050023, that's what we used. Inrush would finish sooner with a smaller bulk cap, so no problem there. The bulk capacitor is after the pass FET, so it has no affect on detection or class.

    Thanks,
    Tom Amlee
    PoE PD Apps Engineer
  • 0 in reply to Thomas Amlee
    Intellectual 470 points
    Hi Tom,

    Funny enough I found a 100uf capacitor which I could fit in my application, now that I have the option to choose between them,which one would be more recommendable?

    Regards,
    Winsu