Is solder a good heat transfer medium?

[leadbelly]

Sorry to crosspost, but it looked like my subject was not going to get an answer:

http://www.diyaudio.com/forums/showt...707#post345707

I want to use LM384's, which are DIP chips using the middle six pins for the heatsink connection. If I were to solder these 6 pins to a generic heatsink, would that be an acceptable bond for heat transfer to the sink?

[sreten]

If you can solder to a generic aluminium heatsink
then you get my Genius Of The Year award.

A copper heatsink is a better bet.

sreten.

[JonPike]

Well, I've heard of, but never tried, using Asprin as a flux for Aluminum.

These kinds of chip are normally soldered down to a pc board, with a broad copper area connected to those pins as an on board sink. So yes, solder is fine, even though it dosen't conduct anywhere near as well as pure copper or Al.. It conducts a hell of a lot better than air!! There's just not that much heat generated in a small chip like this, so no worries...

As Sreten said.. copper would be easiest to work with.. go to the hardware or hobby store and see if you can find some copper or brass sheeting.. dosent have to be very thick (maybe .030" or more) and cut yourself a strip a inch or so long, wide enough to fit across the pins. Do some research to see if needs to stay isolated, or if it's grounded, etc... and keep it from shorting to anything else.. and your done!

I'll have to try that Asprin flux trick one of these days, though, and see if it really works.

[Sch3mat1c]

Pffbbt. Soldering aluminum is easy, just pile on a glob of solder and rosin and scratch up the aluminum surface with the soldering (iron/gun) tip.

If that's too much, you could solder on heavy copper tabs to screw to the heatsink instead. Or install clips to hold the heatsink against the chip ala processor heatsinks.

Tim