I purchased a couple of the TPA3116 boards off of Ebay. The small heatsinks are glued to the chips. Any ideas as to the type of glue they are using. It is soft and pliable which would tend to indicate silicone glue. My guess is this would not result in very efficient heat transfer.
If I pull the heatsinks off, what but be a better glue to use? Would expoxy stick well to the tops of the chips?
If I pull the heatsinks off, what but be a better glue to use? Would expoxy stick well to the tops of the chips?
keep the heatsinks off for a while and determine the need for heatsink, after that evaluate the need for "best" glue 😛
This is probably what was used.
TBS20S - ELECTROLUBE - ADHESIVE, THERMAL BONDING, 2 PART | Farnell element14
It is about the best conductor one can buy.
TBS20S - ELECTROLUBE - ADHESIVE, THERMAL BONDING, 2 PART | Farnell element14
It is about the best conductor one can buy.
Or you can use those double sided adhesive tape like the 3M 8810 type. They come in different sizes and you can also get them in a roll and cut them to sizes. It conducts heat and is electrically insulated (no worry here I guess).
Regards,
Doesn't matter when the heatsinks are so tiny, as is the heat output of TPA3116.
I won't comment on which TIM / blu-tack / toothpaste makes it sound better.
I won't comment on which TIM / blu-tack / toothpaste makes it sound better.
I usally use cpu thermal paste + micro drop of superglue in one of the corners. Works great! Since the heatsink is very small you don't need more than a spec of glue to keep it in place. That way you can twist of the cooler if your going to make some changes to it.
The chip never becomes very hot so you don't heat resisting glue either🙂
I've heard that the white stuff is just window glue^^, so yes its not very good!
The chip never becomes very hot so you don't heat resisting glue either🙂
I've heard that the white stuff is just window glue^^, so yes its not very good!
There is so little heat from these guys anything works. My YBDZ amp has heat sinks held on with scotch double sided thin tape. I think a dab of RTV silicone would be fine. We are talking less than 5 watts max and most of the time less than 1 watt dissipation.
Thanks for all the replies. The chips do run very cool under normal usage. I drove it with a 1 KHz sine wave for 30 minutes at 30 watts PBTL mode and the heat sink became somewhat warm but not too hot to touch.
I like the idea of thermal paste plus a microdot of super glue.The super glue should stick well to both the chip and the heat sink. I think I will pull the heat sink off and replace the silicone (window glue) with thermal paste and super glue.
I will drive it with the sine wave for 30 minutes and take a temperature reading of the heat sink before I remove it. Then repeat the process after the new glue job to see what the difference is.
I like the idea of thermal paste plus a microdot of super glue.The super glue should stick well to both the chip and the heat sink. I think I will pull the heat sink off and replace the silicone (window glue) with thermal paste and super glue.
I will drive it with the sine wave for 30 minutes and take a temperature reading of the heat sink before I remove it. Then repeat the process after the new glue job to see what the difference is.
Assuming the majority of heat coming out of the TPA goes into the heatsink, you won't see much of a difference in heatsink temperature - that's set by the power into the heatsink and the heatsink's thermal resistance.
And remember that silicon can handle much higher temperatures than your finger, most power semiconductors will happily chug along at die temperatures over 100C but you'll burn yourself touching them. Doesn't indicate a problem.
And remember that silicon can handle much higher temperatures than your finger, most power semiconductors will happily chug along at die temperatures over 100C but you'll burn yourself touching them. Doesn't indicate a problem.
I come from the pc overclocking world so I like to keep my IC cool because of the obvious benefits. I also use all the little power the tpa3116 has for extended periods of time when listening too concerts and and having partys. So in such use it pays to have proper heat transfer so the chip doesn't misbehave at bass transients. I've found that the best solution is to use superglue/paste and a copper column into the exterior chassis. That way cooling doesn't stop when the air inside gets luke warm.
Rcbuck, the heat sink actually should get hotter when the heat transfer from the chip is improved😉. You have to measure the ic's temperature to see if that lowers after applying the paste🙂
I can also mention to others that just thin superglue works in most cases (normal use).
Rcbuck, the heat sink actually should get hotter when the heat transfer from the chip is improved😉. You have to measure the ic's temperature to see if that lowers after applying the paste🙂
I can also mention to others that just thin superglue works in most cases (normal use).
In the days of 386 CPU's, the heatsinks were often just glued onto the CPU's with a suitably sized drop of superglue. It seemed to conduct the heat really well and was extremely simple to do, and being superglue, was very fast and usable immediately.
What's wrong with using heatsink glue, a stuff that is designed for this purpose ? Standard cyanoacrylate ("superglue") does not have the best thermal characteristics so using that is beyond comprehension. I guess the reason it always pops up is its availability and the fact everyone knows it contrary to industrial products. Of course cyanoacrylate can be used with added stuff but then you will read "thermal resistance " etc. in its datasheet and it will have a fancy name indicating it is for glueing heatsinks 😉 Drawback of cyanoacrylate is that it needs to be applied between very small gaps like 0.05 mm. JB Weld would be a much better choice if no thermal conductive glue can be found (or when you think the "official" thermal glue for heatsinks is too expensive). JB Weld is not an official product for this purpose but it is usable to 280 degrees celsius which makes it a fine thermal conductive glue with way better properties than cyanoacrylate glue. Please apply it carefully as it has electrically conductive properties.
J-B Weld Twin Tube | J-B Weld
I also use this "official" (meaning the manufacturer specifies it for glueing heatsinks) thermal conductive glue and it is very good:
WLK 5, Thermally conductive adhesive, Heatsinks f.cool, Fischer Elektronik
Please be aware both these products are real glue. Once cured removing the heatsink will be tough if not impossible. In my experience removing the heatsink will mean pulling out the IC from the PCB. No problem for me as glue should perform like that. There are some silicone adhesives out there that behave better than heat conductive paste (but less good than thermal conductive glue) and they offer the possibility to remove the heatsink but why would you ?
J-B Weld Twin Tube | J-B Weld
I also use this "official" (meaning the manufacturer specifies it for glueing heatsinks) thermal conductive glue and it is very good:
WLK 5, Thermally conductive adhesive, Heatsinks f.cool, Fischer Elektronik
Please be aware both these products are real glue. Once cured removing the heatsink will be tough if not impossible. In my experience removing the heatsink will mean pulling out the IC from the PCB. No problem for me as glue should perform like that. There are some silicone adhesives out there that behave better than heat conductive paste (but less good than thermal conductive glue) and they offer the possibility to remove the heatsink but why would you ?
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All types of heatsink glue is basically an insulator compared to copper or aluminium. When I use silver paste (on oc'd cpu)I just apply a see trough layer(1/20th of a mm) to make up for the imperfections in the milling finish in my heat sinks. Sometimes I polish them beforehand. Therefore a super thin layer of superglue is good enough in this setting and also non conductive when spilling. Its really nice that you can remove the heatsink (since you've only used a spec of superglue in the corner)when applying more mods to your favourite amp😉 I found out that to apply the rc analogue power in mod you have to remove the heatsink so you can se what you are doing. It usally involves cutting the ic leg and to solder a resistor/cap directly onto it.
But the biggest reason to recommend superglue/paste is that it is a cheap glue everyone has in their drawer already🙂 You could also swap out the paste to light grease if you you're really cheap🙂. In my opinion this is a bit better than the thick layer that the heatsinks comes with from the factory.
I agree with jean-paul that his way is the professional/most effective way to do it, but since my amps always evolve, like from garage amp to boomblaster amp to birthday gift, I like the possibility to go back and change every aspect of the amplifier.
But the biggest reason to recommend superglue/paste is that it is a cheap glue everyone has in their drawer already🙂 You could also swap out the paste to light grease if you you're really cheap🙂. In my opinion this is a bit better than the thick layer that the heatsinks comes with from the factory.
I agree with jean-paul that his way is the professional/most effective way to do it, but since my amps always evolve, like from garage amp to boomblaster amp to birthday gift, I like the possibility to go back and change every aspect of the amplifier.
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