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TPS7B7702-Q1: What is the max PD(power dissipation) about this device?

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Replies: 4

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Part Number: TPS7B7702-Q1

Dear team,

What is the max PD(power dissipation) about this device like below description? (below picture is other device's datasheet)

Thanks & Best Regards,

Sherry

  • Hi Sherry,

    This looks like it could be a Ricoh device.

    To make sure I make the correct comparisons, can you share the device part number so I can review its datasheet?
    Then I will know what conditions they measured their thermal performance, and I can try to provide a similar performance for the TPS7B7702.

    Thanks,

    - Stephen

  • In reply to Stephen Ziel:

    Hi Sherry,

    Since it has been a week without a reply, we assume that this issue has been resolved.  If this is not the case, please feel free to reply.

    Thanks,

    - Stephen

  • In reply to Stephen Ziel:

    Hi Stephen,

    The picture comes from the datasheet of R1518.

    https://pdf1.alldatasheet.com/datasheet-pdf/view/899036/RICOH/R1518.html

    Thanks & Best Regards,

    Sherry

  • In reply to Sherry Liang:

    Hi Sherry,

    FYI - There is a newer datasheet on the Ricoh website for this part number.
    The new datasheet only calls out the better power dissipation number, so I'm using that value in my comparison.

    The Ricoh component calculates the max power loss at ambient temperature of 25C.
    125C junction temperature is the maximum allowed, so (125-25)/2700mW = 37 C/W Tja, as stated in the Ricoh datasheet.

    Keep in mind that Ricoh's LDO has a recommended max junction temperature of 125C, which is lower than the TI's recommended max at 150C.
    Ricoh's component has a maximum ambient temperature of 105C, which is lower than the TI's recommended max at 125C.
    The data for Ricoh's component is measured up to an ambient temperature of 105C, which is lower than the data for TI's component which is measured up to 125C.

    If your customer does not plan on operating at these temperatures then this comparison will not be that useful, but I thought I would offer it in case it can be helpful.

    A direct comparison to the TI part is possible, but we will use the TI max of 150C junction.
    Ricoh has a value listed at 150C, but since the Ricoh datasheet lists an absolute max temperature rating of 125C, I will not be using that in my comparison.

    The TI Tja is 40.3 C/W and can rise (150C-25C) = 125C.  So the max power dissipation allowed is 125C / 40.3 C/W = 3100mW.
    This is higher than the 2700mW the Ricoh component can dissipate.  The main difference is the absolute max temperature of the TI part is 25C higher than the Ricoh part. 

    Thanks,

    - Stephen