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SN75452B: Request for Dissipation Ratings information of PS package

Part Number: SN75452B
Other Parts Discussed in Thread: ULN2003A, TPL7407LA, SN75158, , SN75140

Dear Technical Support Team,

Could you give me a dissipation Ratings information of PS package?

Datasheet doesn't have it below.

Best Regards,

ttd

  • Hi TTD,

    Thanks for reaching out on E2E. Unfortunately, seeing this is an older device (released in 1967), we don't have detailed thermal information in our database. Can you provide more detail regarding the customer application, we might be able to calculate the thermal dissipation with the information provided in the datasheet.

    If the device hasn't been designed in, I recommend looking at our newer low side drivers including the TPL7407LA and the ULN2003A.

    Thanks,

    Arthur Huang

  • Hi Arthur Huang,

    Thank you for your reply.
    What information should I prepare when you calculate ?
    The number of board layer?
    Kind of board material?

    Best Regards,
    ttd

  • Hi TTD,

    What information are you looking for specifically? Table 7.3 contains thermal information calculations, are you looking for this information or something different?

    Thanks,

    Arthur Huang

  • Hi Arthur Huang,

    Thank you for your reply.

    I'm looking for "power rating (TA=25℃)" and "Derating  Factor Above TA = 25℃" and  "power rating (TA=70℃)" at 7.6 Dissipation Ratings for PS package.

    Best Regards,

    ttd

  • Hi Arthur Huang,

    Do you have any update so far?
    Can I calculate Derating Factor through Thermal information like θJA ?

    I think that Thermal information is based on High-k and dissipation Ratings like deration factor is based on Low-k , right?

    Best Regards,
    ttd
  • Hi TTD,

    I tried working backwards in my calculations to extract the dissipation ratings from the PS thermal information and the junction temperature, but I was unable to get a concrete value. I also looked at our database and was unable to find any dissipation ratings, due to this being an older device. 

    Based on thermal information, since the D package performs slightly worse than the PS package, you could use the D Dissipation Ratings as a conservative estimation of the PS ratings. The PS package should perform better than the results you get with the D package, but this could work as an estimation.

    Thanks,

    Arthur Huang


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  • Hi Arthur Huang,

    Thank you for your reply.

    I found DISSIPATION RATING TABLE of SN75158.

    D and P package are same information with SN75452B and it shows derationg factor for PS package.

    Does it work for SN75452B ?

    http://www.ti.com/lit/ds/symlink/sn75158.pdf

    Best Regards,

    ttd

  • Hi TTD, 

    Yes, that will work. The SN75140 also has dissipation ratings for the PS package, and they have the same values as the SN75158.

    Thanks,

    Arthur Huang