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Old 13th April 2005, 08:03 PM   #1
amt is offline amt  United States
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Default The New T-amp PCB

Okay, its official. The new T-amp PBCs are now being produced without the solder heatsink. Ive had correspondance with a representive at Sonic Impact Technologies, and he stated that the new solderless boards arent a manufacturing error but a change in production. So for the SIs' intended use, the heatsinking isnt neccessay apparently. He was quite helpful and responded quickly to my email and I followed up with a phone conversation. So Ive moved the discussion out of the "faux pas" thread since its not now appropriate.

For those that dont know what Im talking about, check this thread for pictures and a brief discussion.

SI PCB faux pas?

So my next project is to hook one up and see how it fairs with a 4 ohm load for an extended period of time.

amt
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Old 13th April 2005, 10:08 PM   #2
dgo is offline dgo  Netherlands
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Are there any other (component?) changes you can see?
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Old 14th April 2005, 12:49 AM   #3
Pano is offline Pano  United States
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Default Re: The New T-amp PCB

Quote:
Originally posted by amt
Okay, its official. The new T-amp PBCs are now being produced without the solder heatsink.
Thanks AMT. You can ignore my email and the post on the other thread.
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Old 14th April 2005, 07:12 AM   #4
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Man.. The new PCBs look so much cleaner than the old ones. Great stuff!

Thanks for the heads up, AMT!
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Old 14th April 2005, 12:49 PM   #5
shelt is offline shelt  United States
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I've modded two SI boards -- one with the solder blobs, and a new one without. I've been using those self-adhesive aluminum heat sinks mentioned in another thread.

I didn't do a scientific test, but the new "blobless" board definitely heats the sink to a higher temperature than the older board.

These little heat sinks are the EXACT size of the Tripath chip, and stick right on. They even come in difeferent colors!

Since they are very cheap insurance, I suggest every modder pick up a few!

Rich

Here's a link: http://cgi.ebay.com/ws/eBayISAPI.dll...sPageName=WDVW
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Old 25th August 2005, 12:15 PM   #6
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hey......i noticed it has been a while since anyone mentioned about the heat issue with the chip...........just wondering if the micro heatsinks from the dealer on ebay worked....if they did, was a heatsink mounted on top AND below the chip...?......justa wonderin'
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Old 25th August 2005, 12:56 PM   #7
KT is offline KT  United States
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Eric,

The heatsink sticks right onto the top of the chip. The chip sits on one side of the board, so there's no way to stick one on the bottom side.

On the older boards, the solder blob sits all around (maybe under?) the chip and helps to dissipate the heat. Looks like the new boards have small holes drilled through the areas where the solder slug used to sit, but from what I've read on the boards, this little bit of airflow doesn't cool the chip as well as the slug.

Best,
KT
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Old 25th August 2005, 03:11 PM   #8
amt is offline amt  United States
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The holes definately dont provide enough airflow to cool the chip. Heatsinking is a must if the amp is operated much past a watt or two. My solution has been to flow solder on the top of the board and onto the copper tap that protrudes from the sides of the chip. One side is blocked by the power/input wires but the other side is open. While the puddle of solder is still hot, I attach a piece of copper to it which is about 1/2 x 1/2 x 1/8" . This piece of copper bar pulls the heat from the chip nicely and dissipates it well. I recently started attaching the copper heatsink to the bottom of the board by filling the holes under the chip with solder. I keep a 20lb piece of aluminum chilled in the freezer to pull some of the heat from the board once the soldering is done, since it generates quite alot of heat. All my amps have been built this way since the slug was eliminated.

amt
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Old 25th August 2005, 04:17 PM   #9
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Had a bad experience with a 'stick on' heat sink before that was forced on me, on a 32 bit RISC Controller Design I did. After enough power/heat cycles, the adhesive gave up and the heat sinks turned into big chunks of bad stuff rolling around on the circuit boards while the processors roasted themselves to death.
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Old 26th August 2005, 01:02 AM   #10
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Use Arctic Silver Epoxy, rather than the crappy adhesive tape. It'll stick to the chip forever and it has a considerably better thermal coefficient than most self adhering TIMs.
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