Copper heatsink tweak - Thermaltake Copper Heatsinks

[adhoc]

Originally posted by mrjam
Ground loops aren't generated by single shields connected each indipendently at one single gnd point.

ah... star grounding. i get it.

[tubenut]

What about resonance? Would these heatsinks not work as nice tuning forks stuck to the top of the dac chip inducing mechanical vibes?

Heard somewhere that the internal sink on the TDA1541 can be excited to resonate hence Naim took some trouble to specifically isolate the 1541 from vibration on the original CDS...

Just hearsay.....

[Sonusthree]

Surely the heavy copper and the I.C. would have different resonant frequencies which would help avoid resonance.

Also I think the epoxy should act as a form of constrained layer damping.

[poynton]

Originally posted by adhoc


ah... star grounding. i get it.

No, just individual grounds in close proximity to the chip.

Andy

[martin clark]

Looks like a good idea Ruach, esp. for the old Philips chipset (SAA7220 / TDA1541) which run hot - I must find some and try this

Heard somewhere that the internal sink on the TDA1541 can be excited to resonate hence Naim took some trouble to specifically isolate the 1541 from vibration on the original CDS...

Yes they did - in fact all their CD players (except the CD3, 3.5, 5 and 5i/ 5x) have sprung suspension for the PCBs!

[Ruach]

Hey guys,

Do try it out and see if this tweak works for you. It is cheap and it is very easy to implement.

You can either ground it or if you are lazy like me, stick it on the chips and do the grounding another time.

The copper heatsinks are about 2.5 to 3mm thick and they are quite heavy (relatively to the aluminium heatsinks).

The fins are too short to act as a tuning fork and even if this is the case, I am sure that you guys can find a way to damp it.

In my crude experiments based on a handphone as the generator of EMI/RF, I found that thicker copper sheets provide better protection from EMI/RF.

FYI, the Arcam Black Box 1 and 2 have sprung suspension for their TDA1541A chips too.

[Sonusthree]

Well,
My Thermaltake copper heatsinks arrived today but they are diferent to the ones pictured above. The ones that I have bought have a square base and unfortunately are pretty incompatible with the I.C.'s in my CD player. Especially as they are SMD devices.
I have attached 2 of these across four regulators that lay flat on the PCB. So that 2 regs share 1 heatsink. I know it's probably a waste of time and money but what else can I do with them?!!

They are pretty cool things in the flesh though and are surprisingly heavy and rugged for their size. The adhesive sticks fairly well but leaves the sinks able to be twisted slightly.
I'm pretty sure they're going nowhere though unless I drop my player!!
If anyone wants to get some of these then just make sure they are the right version.
Cheers,
S3.