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TPA3126D2: Possible Alternate Heat Sinks

Part Number: TPA3126D2
Other Parts Discussed in Thread: TPA3116D2, TPA3130D2, TPA3118D2, TPA3220, TPA3128D2

I have been testing a TPA3126D2EVM eval board for an upcoming project. Relevant information: 400kHz switching frequency, gain is 26dB, PVCC is 24V, no PLIMIT set, and I'm using an AP2700 for signal generation and loading/analysis.



My goal is to be able to drive a 20W/4Ω continuous 1kHz sine on both output channels while staying at or below 100°C on the chip. This is certainly possible with the eval board's provided heat sink, ATS-TI1OP-521-C1-R1; however, it is much too large for our future design, which will be placed within a small enclosure with multiple other PCBs. Are there other heat sinks that you could recommend that have a lower vertical height (maybe closer to 0.5") that work well with HTSSOP packages?

I've had difficulty looking for heat sinks specifically for HTSSOP or TSSOP online. I've tested a few BGA pin fin heat sinks with the eval board, but they either didn't provide enough thermal relief or were comically over-sized or awkward fitting.

Or is there perhaps another TI chip that has better thermal performance for this application? Sorry for any lack of details!

  • Hey Daniel, 

    I understand your limitations, we do not implement heat sinks with such a low vertical height. 

    However, we do have options that are pad down and the heat will dissipate into the board instead of into a heat sink. A good example of this is the TPA3116D2, which implements the relevant information listed above. 

    Worst case scenario,  you can always just mill down the heat sink to fit your small enclosure. I am not sure if it will be able to stay below 100C but worth a try to see if that is a possible solution. 

    All the best,

    Carolina 

  • Hi Carolina,

    Thanks for the response! Honestly, it seems like a thermal pad down package is the solution here. Milling/Ordering a custom heat sink unfortunately isn't possible with this project.

    - Dan

  • Hello Dan, 

    I have this message from you in my emails but I am not able to see it in this thread: 

    "Hi Carolina,

    Quick follow-up question: The datasheet from your link seems to cover the TPA3116D2, TPA3118D2, and TPA3130D2. The 3116 looks like it's a thermal pad up package, but the 3118 seems to be a thermal pad down package, which is what I'm interested in. But do all the figures and typical characteristics apply to all three of the ICs? It seems that the 3118 is lower power than the 3116, but the figures and graphs don't seem to specify which model they refer to!

    - Dan"

    You are correct, I linked the wrong part and after further investigation I am not sure that TPA3118D2 will be able to support continuous 20W into a 4 ohm load. However, I think one of our high power parts will be a better suit. 

    The TPA3220 is pad down and fits a good majority of your criteria, except that it switches at 480 kHz instead of 400 kHz and has gain settings of 24dB, and 30dB, but not 26 dB.

    Let me know if this works for you. 

    All the best, 

    Carolina 

  • Hi Carolina,

    I actually deleted that post after deciding that the TPA3128D2 would probably best suit my application; but if you doubt the 3118's capability to drive 20W continuous into 4 ohms, should I be worried about the 3128's ability to as well? It seems that they have similar power capabilities, but the 3128 has improved idle current draw and alternate PWM configuration.

    I have already ordered eval boards for the 3128, but can also order an eval board for the 3220 is you think the 3128 is insufficient.


    - Dan

  • Hey Dan, 

    The reason I suggested a higher power part is really based off of your definition of "continuous". By this I mean, do you want to be able to produce a 20W/4ohm 1kHz sine wave for 2 minutes or 10 minutes? 

    The pad down devices have the limitation of surface area in heat dissipation because they use the PCB for heat dissipation, as opposed to a heat sink which provides a lot more surface area. 

    That being said, a higher power part is designed to handle power levels much higher than 20W, so they are a "safer" choice in the continuous application. 

    All the best, 

    Carolina 

  • Hi Carolina,

    I admit I'm not entirely sure how long I need the device to operate at 20W/4ohm continuously, but I had roughly set a goal of 5 minutes. I think my best course of action is to order a TPA3220 eval board and compare thermal performance (and price) side by side with the TPA3128D2.

    You've been very helpful. Thank you!

    - Dan