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UCC27517: operating ambient temperature range of UCC27517DBVT

Part Number: UCC27517

Dear Specialists,

My customer is considering UCC27517DBVT and has questions.

I would be grateful if you could advise.

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Thermal information,
Could you please let me know

(1)detail of evaluation board of si-taJA and si-taJC(top) and si-taJC(bot)
1p or 2S2P, board dimension,board material, copper thickness etc.

(2)How could I think about operating temperature range.
The datasheet says only junction temperature range.

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I appreciate your great help in advance.

Best regards,

Shinichi

  • Hello Shinichi,

    Thanks for reaching out.

    1. The link below discusses thermal considerations of TI devices.

    http://www.ti.com/lit/an/spra953c/spra953c.pdf 

    2. The junction temperature range in the datasheet represent the operating conditions of the device as switching transitions cause power dissipation across the driver, which induce a temperature which must be within this specified junction.

    Using the link below, you can extract your max ambient temperature at a given switching frequency, VDD, load, etc...

    https://e2e.ti.com/support/power-management/f/196/p/788867/2917563#2917563 

    Regards,

    -Mamadou

  • Hi Mamadou,

    Thank you for your reply.

    Could you please advise more detail.

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    1. According to the SPRA953C, two thermal resistance values of 1s and 2s2p are shown.

    1S and 2S2P are understood as the measured board conditions specified by JEDEC.

    On the other hand, the UCC27517 data sheet does not clearly state which board, 1S or 2S2P, was used.

    Please let us know which board was used, 1S or 2S2P, in UCC27517, including the board size and copper thickness.

    The customer'd like to know the information.

    2, The operating ambient temperature range is not specified.

    It is necessary to calculate by device power dissipation, si-taJA and junction temperature.

    My understandig is correct? 

    ---

    I appreciate your great help and cooperation.

    Best regards,

    Shinichi

  • Hello Shinichi,

    1. We use a 2s2p board in the simulations to determine thermal.

    2. The operating ambient temperature is not specified because our drivers specifications are based on the junctions operating conditions that we control. Calculating power dissipation will give a more accurate ambient temperature. 

    Regards,

    -Mamadou 

  • Hi Mamadow,

    Thank you for your reply.

    We understand 2S2P board is used for determining thermal data.

    I could find an application note(SZZA017A) described 2S2P boards.

    It is described Trace thickness, Trace length, PCB thickness, PCB width, PCB length and Power/ground-plane thickness.   

    http://www.ti.com/lit/an/szza017a/szza017a.pdf

    Could we introduce this document to the customer as the measurement condition of thermal resistance. 

    I appreciate your great help and cooperation.

    Best regards,

    Shinichi

  • Shinichi,

    THe document is available on ti.com therefore you may share with customer.

    Regards,

    -Mamadou

  • Hi Madadou,

    Thank you for your reply.

    We'll share your answer and the application note with the customer.

    We appreciate your great help and cooperation.

    Best regards,

    Shinichi