Copper heatsink tweak - Thermaltake Copper Heatsinks

[Ruach]

There is a quick tweak that you guys can try.

Thermaltake sells copper ram heatsinks for DRAMs. These heatsinks comes with a special 3M heat conductive adhesive to allow one to stick it securely to the any chip.

These heatsinks are rather thick and they should also act as good shields for EMI/RF shielding purposes.

The heatsinks are retailing at a couple of buck for a pack of 8.

You can stick them to your dac, receivers, opamps, digital filters etc...

[Ruach]

Another photo of the copper heatsinks

[Sonusthree]

Hi Ruach,
Sounds like a good idea. I'm sick of messing around with self adhesive copper tape!!

I'm wondering now whether or not there is any benefit or disadvantage to cooling chips in a DAC or similar?
Is it preferable to keep them as cool as possible or keep them at a slightly higher temperature (without these heatsinks)?

Also in the UK these cost around 8 pounds
(The similar blue anodised aluminium version is cheaper and lighter but obviously diificult to solder.)
I'm definitely interested for the RFI alone but the thermal properties got me thinking.
Any ideas?

[wa2ise]

Originally posted by Ruach

These heatsinks are rather thick and they should also act as good shields for EMI/RF shielding purposes.

You'd need to connect these heat sinks to ground to get the EMI/RF shielding. Wires to connect them to ground should be as short as you can easily make them, like a few centimeters long. But be careful you don't create any ground looks if you use multiple wire connections.

[Ruach]

Yep. To get proper shielding, you have to connect the heatsink to the ground via a short length of wire.

I did an experiment without the ground connection and I found out that as long as the copper sheet is thick, there will be some form of shielding.

In Singapore, a set of 8 copper heatsinks goes for 6 euros. But due to a lack of demand, the distributor has decided not to bring them in anymore.

I am trying to do a small group buy to bring some of these fellows in.

[Sonusthree]

Originally posted by Ruach

I did an experiment without the ground connection and I found out that as long as the copper sheet is thick, there will be some form of shielding.

I'm very surprised to hear that.

I've used copper foil for shielding in the past but soldering to it ( before application of course) often degrades the adhesive and makes a good reliable fix quite difficult.
Any opinions on the issue of temperature?

[adhoc]

how about connecting the heatsinks in 'series' with wires, and then to ground? wouldn't that avoid any issues with ground loops?

anyway, for what it's worth, this sounds like a good idea. heat is the enemy of electronics; the less, the better for both lifespan and value drift. the emi/rfi protection is just icing on the cake imo.

[seoman]

Originally posted by Sonusthree

I've used copper foil for shielding in the past but soldering to it ( before application of course) often degrades the adhesive and makes a good reliable fix quite difficult.
Any opinions on the issue of temperature?

The glue used with heatsinks is based on a epoxy base.
And it can be aplied after soldering.
i also think the epoxy can handle the soldering temparatures.

removing the epoxy glued heatsinks can be done by freezing the the components. When frozen use some force.
(worked fine on my graphicscard)

[adhoc]

Originally posted by seoman
removing the epoxy glued heatsinks can be done by freezing the the components. When frozen use some force.
(worked fine on my graphicscard)

plus use a twisting motion (like opening a jam jar's screw-top lid) rather than a pulling motion (like opening a soft drink can's tab) when removing the heatsink to prevent tearing components off pcbs.

[mrjam]

I've used copper foil for shielding in the past but soldering to it ( before application of course) often degrades the adhesive and makes a good reliable fix quite difficult.

The purpose of shielding is to shunt RFI to ground. How can you achieve this whithout connecting the copper heatsinks close to the gnd pin of the underlying IC? So soldering is inevitable! Ho cares about adhesive ..buy a new epoxy kit!!

how about connecting the heatsinks in 'series' with wires, and then to ground? wouldn't that avoid any issues with ground loops?

no ..no ..no!! Each shield must be connected close to the underlying IC. Otherwise you generate a RF mess radiating everywhere!
Ground loops aren't generated by single shields connected each indipendently at one single gnd point.