Looking for heatsinks

[Heisenberg]

I'm looking for a heatsink for an LM3886 guitar amp I'm planning on building.

Also it'd be nice to get some big ones that'd dissipate head really good for some TDA2030s.

[jackand08]

Depending on where you live, there are some good online retailers that sell some very good sized-and priced-heatsinks. One place to try would be Jaycar Electronics. They are from Australia but ship worldwide for a competitive price (if you don't mind having to wait for your goods). Another to try would be Farnell who also have an excellent range but are a bit higher priced compare to Jaycar when you consider what you are getting.

For a mono LM3886 amp, you would need a heatsink of no more than ~1°C/W thermal resistance, but if you are planning to drive the amp hard (guitar use), then you would want a heatsink with no more than 0.75°C/W thermal resistance (again for mono only).

[Heisenberg]

thanks!

[gootee]

There used to be a guy on ebay who sold really nice big extruded ones by the foot. You can also usually scrounge some decent ones from junk equipment. You could also check at places like Antique Electronic Supply (try Google). They also have a lot of other guitar-amp-related stuff. Sorry, I don't have either of the links handy. Maybe someone else will post them.

[Looneytunes]

Originally Posted by gootee

There used to be a guy on ebay who sold really nice big extruded ones by the foot.

He's still there. I saw him today. His seller name is barrredboss.

Looney

[Heisenberg]

Eh, I'm kinda new to this, and I'm having trouble finding a heatsink with those charictaristics. I don't even really know what that stuff means. Or how to find one like that that'll fit the LM3886 or follow it's datasheets heat sinking specs. The sites I've looked through have like 2,000 different heatsinks to sort through.

[Heisenberg]

gootee, I've looked at tubesandmore.com (antique electronic supply) for heatsinks and don't remember finding any heat sinks at all.

[gootee]

Originally Posted by Heisenberg

gootee, I've looked at tubesandmore.com (antique electronic supply) for heatsinks and don't remember finding any heat sinks at all.

OK. But search for barrredboss on ebay.com. His stuff will do what you need!

[jackand08]

Originally Posted by Heisenberg

Eh, I'm kinda new to this, and I'm having trouble finding a heatsink with those charictaristics. I don't even really know what that stuff means. Or how to find one like that that'll fit the LM3886 or follow it's datasheets heat sinking specs. The sites I've looked through have like 2,000 different heatsinks to sort through.

The thermal resistance of a heatsink is the temperature rise that of the heatsink compared to the surrounding air temperature (ambient). For example, a heatsink with a 2°C/W rating, this would mean that for every 1 watt of heat dissipated (from say, a transistor), the heatsink temperature will be 2°C higher than the ambient temperature. A lower thermal resistance means that the heatsink can dissipate more heat but in the case of natural convection (i.e. not force cooled) heatsinks, this means that it will be much larger.

On Farnell's website, under the natural convection heatsinks, there should be a filter labelled "Thermal Resistance" (at least on the UK site there is). Underneath this, you can filter the 2000 or so heatsinks that the supply. When you've finished, just click on the "Show Results" button and that should bring up a much more refined selection of parts matching the criteria you specified.

If you would like to order from Jaycar, their heatsink catalogue no. HH8555 would be fine for an LM3886 amp and shouldn't get too hot if the amp was driven hard.

[Heisenberg]

Thanks. I just ordered that one from Jaycar. Expensive.