• State Resolved
  • Locked Locked
  • Replies 5 replies
  • Answers 2 answers
  • Subscribers 64 subscribers
  • Views 316 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

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.

TPS22950: Functional difference between TPS22950-Q1 and TPS22950C

Evan Shultz
Prodigy 30 points
Part Number: TPS22950

When I began looking for a current-limited load switch I found TPS22950-Q1. It is only available in SOT23-6.

Recently, the TPS22950 datasheet was updated to add the SOT23-6 package for the non-automotive part.

I am not seeing any significant functional difference. For example, Iq,VIN is 44uA typical vs 40uA and the OQD resistance changes a bit with supply voltage above 1.8V and the switching characteristics are a bit slower for the automotive part, but those differences are small and aren't significant to me. (If they are even real.) Is there a notable functional difference between the 'regular' TPS22950 and -Q1 version? Ultimately, I'm wondering if I can also use the non-automotive part in my non-automotive application where the regular TPS22950 is otherwise suitable.

  • +1
    TI__Genius 15625 points

    Hi Evan, 

    Other than the differences you've mentioned, another difference is the non-QOD version's ILIM range. The non-QOD version's ILIM range narrows to 0.5A to 3.5A rather than the Q-1 version's 0.05 to 3.5A. 

    Other than these differences, there is no notable functional difference between the TPS22950C and TPS22950-Q1.

    If these differences, including the lack of automotive qualification is not significant to your system, I would recommend using the TPS22950C device. 

    Best Regards, 

    Elizabeth 

  • 0 in reply to Elizabeth Higgins
    Prodigy 30 points

    Hi Elizabeth,

    Thank you. I have additional follow-up questions.

    I notice that TPS22950 and TPS22950C have the same behavior in the table in section 5 but a different ILIM range. Is that correct? The *C part can't go down to 50mA like the -Q1 part? If so, can you share what happens if RLIM is set for a current below 0.5A on the *C part?

    In addition, how can I find out which TPS22950 parts have the QOD? The front page nor section 5 nor section 7.5 of the datasheet mention this feature being exclusive to only some of the non-Q1 members of the TPS22950 family so I expected they all had it. The block diagram in the -Q1 datasheet shows the QOD feature but the block diagram in the non-Q1 datasheet does not. Your comment above makes me think that the *L and *C parts do not have QOD but I don't see anything in the datasheet that tells me this. Am I missing where it is spelled out?

    It appears that TPS22950C is functionally different than TPS22950-Q1. My expectation was that they were the same but without automotive testing/qualification, but it appears I had not fully understood the very real differences earlier.

  • +1 in reply to Evan Shultz
    TI__Genius 15625 points

    Hi Evan, 

    Yes the same ILIM values are shown for the TPS22950 and TPS22950C. However for the TPS22950C and TPS22950L, these devices were not tested for ILIM <0.5A and as such we can only recommend the ILIM range 0.5A to 3.5A. 

    With regard to the QOD feature, I understand the confusion and we will get the block diagram to include the QOD block. 

    Rest assured, all TPS22950 versions (TPS22950, TPS22950L, and TPS22950C) have QOD. 

    The differences between the TPS22950C and TPS22950-Q1 are the slight difference in QOD, IQ, and the difference in current limit range. 

    Best Regards, 

    Elizabeth 

  • 0 in reply to Elizabeth Higgins
    Prodigy 30 points

    Hi Elizabeth,

    Thank you.

    Then can you please clarify this statement above: "The non-QOD version's ILIM range narrows..."? Your second post above states that all TPS22950 have QOD, but your first post intimates some TPS22950 versions do not have QOD.

    Lastly, is there any reason why the behavior of the *L and *C parts would not be the same as the vanilla TPS22950 at RLIM values that set the current below 0.5A? Is the current limit value expected to be the same, it's just not tested and guaranteed?  (If that is the case, the datasheet doesn't mention anything at the bottom of page 6 where RILIM = 19.2k that this doesn't apply to the *L and *C parts. It would be easy to read the front page miss that important information which is only captured on page 4, from what I can find in the datasheet.)

  • 0 in reply to Evan Shultz
    TI__Genius 15625 points

    Hi Evan, 

    Apologies as I see the confusion now. The statement "The non-QOD version's ILIM range narrows..."? was a typo on my part. I meant to say "The non-Q1 version's ILIM range narrows." All TPS22950 devices have QOD. 

    You are correct the difference is for the TPS22950C <0.5A current limit is not tested and guaranteed. I agree a clarifying statement in the electrical characteristics section would be helpful to confirm the TPS22950C is not tested and guaranteed for <0.5A current limit operation so I will work to get that added. 

    With regard to the TPS22950L, since it current limits differently than the TPS22950, we instead specify the output current limit peak down to 0.5A. 

    Best Regards, 

    Elizabeth