Hi Guys!🙂
First of all, please try to forgive me for my bad english😱!!!
I would like to ask you what is the best type of metal for the best heat dissipation of an old (obsolete) audio integrated transistor ( TCA940, 10 watt max audio transistor).
Unfortunately the TCA940 heats a lot, so I want to build a very nice and useful (handmade-DIY) heat-sink for this transistor, because the (rare) common heat-sinks for the TCA940 on the market have a shape that doesn't fit the available space in my small circuit board.
I've a good idea how to do, but I've no idea about the best metal to use for the best heat dissipation.
I was thinking to use copper.
What do you think about copper as a possible solution? or does exist some other higher quality metal for the heat dissipation? I don't care about the price!
Please guys, help me!!! give me your opinion!
Thank you in advance for your kindness and patience!
Best Regards
First of all, please try to forgive me for my bad english😱!!!
I would like to ask you what is the best type of metal for the best heat dissipation of an old (obsolete) audio integrated transistor ( TCA940, 10 watt max audio transistor).
Unfortunately the TCA940 heats a lot, so I want to build a very nice and useful (handmade-DIY) heat-sink for this transistor, because the (rare) common heat-sinks for the TCA940 on the market have a shape that doesn't fit the available space in my small circuit board.
I've a good idea how to do, but I've no idea about the best metal to use for the best heat dissipation.
I was thinking to use copper.
What do you think about copper as a possible solution? or does exist some other higher quality metal for the heat dissipation? I don't care about the price!
Please guys, help me!!! give me your opinion!
Thank you in advance for your kindness and patience!
Best Regards
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It would be worth simulating the heatsink with a thermal calculator, but I don't know of a good one to suggest.
Since you said you don't care about price, diamond has a much higher thermal conductivity than copper
Copper is certainly good enough, it is better than the normally used aluminum.
Since you said you don't care about price, diamond has a much higher thermal conductivity than copper
Copper is certainly good enough, it is better than the normally used aluminum.
Thermal Conductivity of Metals, Metallic Elements and Alloys
Copper is the best of the “reasonable” materials, though getting more expensive by the day lately. Silver is even better if price is truly no object
Copper is the best of the “reasonable” materials, though getting more expensive by the day lately. Silver is even better if price is truly no object
Aluminium makes the most sense.
It's not too heavy, not too expensive and the performance is quite good.
You're going to get most of your performance improvements from increasing the surface area of your heatsink.
It's not too heavy, not too expensive and the performance is quite good.
You're going to get most of your performance improvements from increasing the surface area of your heatsink.
Starting from the beginning: what machinery do you have available?
You mention a metal fabrication process, so:
* milling machine? Not necessarily CNC but it definitely helps.
* cold rolling laminator? (to make metallic sheets the thickness you need)
Plus motorized shears + folder + puncher (I have all 3 for my own chassis and heatsinks)
* metal extruder? (plus suitable dies to extrude finned heatsinks)
* metallic die molten metal injector? plus suitable dies plus access to a milling machine to get flat surfaces.
A copper plate with aluminum heat sinks bolted to it ( with heat sink compound in the joint ) should work well.
You might make the heat sink out of copper sheet (roofing flashing?) and solder it right to the tabs on the IC.
It's not about the metal. You are normally dumping heat to AIR. You want a LOT of Surface Area. And a good path from small device to large air.
Aluminum works very well up to very high power density because it is economical to buy and shape. Do Copper if you wish; Copper does make a little sense for a "spreader" under the Silicon.
Aluminum works very well up to very high power density because it is economical to buy and shape. Do Copper if you wish; Copper does make a little sense for a "spreader" under the Silicon.
Does it have to be a metal?
Diamond is best but a little hard to machine.....
Copper is a lot better than aluminium.....and silver a little better than copper.....but still significant. Even gold is better than aluminium. Pure gold is easy to machine.....I think..
Top 10 Thermally Conductive Materials - Thermtest Inc.
Diamond is best but a little hard to machine.....
Copper is a lot better than aluminium.....and silver a little better than copper.....but still significant. Even gold is better than aluminium. Pure gold is easy to machine.....I think..
Top 10 Thermally Conductive Materials - Thermtest Inc.
Add to check the datasheet it has been a very long time since I last saw one of these buggers
The IC has a surface area of 20x6.3mm so I would suggest using an heatsink from a old computer motherboard chipset (cut to size) or ebay is your friend
High Quality Aluminium 20*20*16mm Heatsink Heat Sink Radiator for IC MOSFET SCR | eBay
The IC has a surface area of 20x6.3mm so I would suggest using an heatsink from a old computer motherboard chipset (cut to size) or ebay is your friend
High Quality Aluminium 20*20*16mm Heatsink Heat Sink Radiator for IC MOSFET SCR | eBay
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TIL... "...diamond is a good conductor of heat because of the strong covalent bonding and low phonon scattering."
Huh. I never really thought about diamond as a thermal conductor, and I even spent a few years in a semiconductor epitaxy nanotech lab. That's pretty cool. But yeah, even silver would be super expensive (for large heatsinks). And like others have said, the challenge tends to be more around maximizing surface area and airflow rather than the metal itself. Also, the interface to the component for cooling is still important (good thermal paste). Bang for buck, I'd be inclined towards copper.
Huh. I never really thought about diamond as a thermal conductor, and I even spent a few years in a semiconductor epitaxy nanotech lab. That's pretty cool. But yeah, even silver would be super expensive (for large heatsinks). And like others have said, the challenge tends to be more around maximizing surface area and airflow rather than the metal itself. Also, the interface to the component for cooling is still important (good thermal paste). Bang for buck, I'd be inclined towards copper.
thank you very much to all, guys! for your support!: wave2:
This is the small ampli circuit board with the two TBA810 transistors that I want to up-grade by replacing them with the equivalent bigger TCA940N.
So one of the pictures shows you the original amp board.
The other picture shows you the idea of what I want to do, when I'll mount the new TCA940, in order to get a bigger heat dissipation surfarce by adding three copper laths to the original small heat-sinks in the ampli board.
The piece of paper you see in the second picture, in practice, will be one of the three copper laths I want to attach to each of the three sides of the original heat-sinks, by using a small screw with a bolt.
Of course I'll insert thermal paste between the new copper laths and the original heat-sink surface.
This is my project. I know my english is very bad, but I hope you understand what I want to do!
Does this up-grade work in your opinion? It doesn't seem a very complicated project to realize, at least I think so🙄.Please let me know!
Thank you again for your precious support!
This is the small ampli circuit board with the two TBA810 transistors that I want to up-grade by replacing them with the equivalent bigger TCA940N.
So one of the pictures shows you the original amp board.
The other picture shows you the idea of what I want to do, when I'll mount the new TCA940, in order to get a bigger heat dissipation surfarce by adding three copper laths to the original small heat-sinks in the ampli board.
The piece of paper you see in the second picture, in practice, will be one of the three copper laths I want to attach to each of the three sides of the original heat-sinks, by using a small screw with a bolt.
Of course I'll insert thermal paste between the new copper laths and the original heat-sink surface.
This is my project. I know my english is very bad, but I hope you understand what I want to do!
Does this up-grade work in your opinion? It doesn't seem a very complicated project to realize, at least I think so🙄.Please let me know!
Thank you again for your precious support!
Attachments
A lot has to do with the nature if the heat to be dealt with. If the heat comes from high power with a low duty cycle, a material like copper with high specific heat will work nicely as a heat reservoir until heat can be transferred to the air. Continuous power just needs high conductivity and surface area. Almost all heat sinks are aluminum, while transistor packages I believe use kovar.
> TCA940, 10 watt max
That is an IC for speech/music. While it can dissipate >5W on test-tone, it will not average even 2W in the loudest parts of speech/music. It will usually be fine with finger-tip PCB copper pads. (I have used a lot of LM380 and LM377 this way.) I have also cut 2cm squares of copper roof flashing and soldered to the tabs. (Copper because it solders well, and this much copper costs pennies.)
Your TCA940 even has thermal protection. If it is not cutting-out, it is not "too hot".
That is an IC for speech/music. While it can dissipate >5W on test-tone, it will not average even 2W in the loudest parts of speech/music. It will usually be fine with finger-tip PCB copper pads. (I have used a lot of LM380 and LM377 this way.) I have also cut 2cm squares of copper roof flashing and soldered to the tabs. (Copper because it solders well, and this much copper costs pennies.)
Your TCA940 even has thermal protection. If it is not cutting-out, it is not "too hot".
Copper is a pain to drill and tap. I have broken more taps in copper than I care to admit. Aluminum OTOH, easy peasy. For most applications, Al is the way to go. Before you DIY it, consider surplus CPU coolers. I use these for Class AB without a fan. For Class A, add a Noctua fan and it can handle 90w easily.
Dell Precision T3500 T5500 T7500 Workstation LGA 1336 Processor Heatsink T021F for sale online
Here I use them with a 50w Class AB "Xmas Amp" TDA7293 chipamp giveaway and it works beautifully.
Dell Precision T3500 T5500 T7500 Workstation LGA 1336 Processor Heatsink T021F for sale online
Here I use them with a 50w Class AB "Xmas Amp" TDA7293 chipamp giveaway and it works beautifully.
Attachments
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Thank you guys!
You're right about the incredible price of the copper: eek:
It's shamefully expensive...I didn't believe so much!!!: Ohno:
So I would to use another type of metal less valuable.
Does a normal and common aluminium work? Thank you guys for your patience:cenno:
Best Regards!
You're right about the incredible price of the copper: eek:
It's shamefully expensive...I didn't believe so much!!!: Ohno:
So I would to use another type of metal less valuable.
Does a normal and common aluminium work? Thank you guys for your patience:cenno:
Best Regards!