I've just started building a Gainclone amp. Currently I am just experimenting with a single chip (mono) trying to get my head around ground loops etc. but my LM3875 chip is getting really warm.
I am using a 240v - 2 x 18V Toroid, and currently using a bar of aluminium 90mm x 30mm x 10mm.
I eventually want to make my own enclosures for my amps, and was originally going to just bolt the chips to the case, but maybe just plain old aluminium won't be good enough.
Would this be any good:
FISCHER ELEKTRONIK|SK 100/100 SA|HEAT SINK, 100MM, 1.5°C/W | Farnell United Kingdom
It says : Thermal Resistance:1.5°C/W and the calculation I did on the Overture Design Guide said for a 6 ohm load that I need 3.08C/W.
I don't understand C/W, so do I go lower or higher to be on the same side.
Or maybe this one:
http://uk.farnell.com/fischer-elektronik/sk-92-50-sa/heat-sink-50mm-1-9-c-w/dp/4621566?Ntt=4621566
This would make my case look better
Thanks
I am using a 240v - 2 x 18V Toroid, and currently using a bar of aluminium 90mm x 30mm x 10mm.
I eventually want to make my own enclosures for my amps, and was originally going to just bolt the chips to the case, but maybe just plain old aluminium won't be good enough.
Would this be any good:
FISCHER ELEKTRONIK|SK 100/100 SA|HEAT SINK, 100MM, 1.5°C/W | Farnell United Kingdom
It says : Thermal Resistance:1.5°C/W and the calculation I did on the Overture Design Guide said for a 6 ohm load that I need 3.08C/W.
I don't understand C/W, so do I go lower or higher to be on the same side.
Or maybe this one:
http://uk.farnell.com/fischer-elektronik/sk-92-50-sa/heat-sink-50mm-1-9-c-w/dp/4621566?Ntt=4621566
This would make my case look better
Thanks
Last edited:
I recommend that the National value be doubled, i.e. 3.08C/W becomes 1.5C/W to keep the chip cooler than absolute maximum rating.It says : Thermal Resistance:1.5°C/W and the calculation I did on the Overture Design Guide said for a 6 ohm load that I need 3.08C/W.
For this the 1.5C/W would be ideal.
If you want to mount two chipamps on the same heatsink then adopt 0.7 to 0.8C/W
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.