View Full Version : what gets hot?

Fred Hawkins
08-31-2007, 06:07 AM
Idle curiosity.

I am considering hot gluing a µSD adaptor to the top of the big Prop chip. I figure that there's actually just a small-ish part of the dip that needs to be·air cooled and I assume that it's in the middle. (Rest of solution: spot solder pre-tinned resistors to appropiate adaptor contacts, insert other ends of resistors into appropriate breadboard locations.)

Is there any reason I shouldn't put a hat on my prop?

Paul Baker
08-31-2007, 06:12 AM
The chip doesn't need any cooling outside the most extreme examples, so there shouldn't be any reason you couldn't attach a uSD socket on it.

Paul Baker (mailto:pbaker@parallax.com)
Propeller Applications Engineer
[/url][url=http://www.parallax.com] (http://www.parallax.com)
Parallax, Inc. (http://www.parallax.com)

08-31-2007, 01:01 PM
When checking the power consumption some month ago, I used 8 COGs working @ 80MHz and draw additionally 160 mA through 8 20mA LEDs. The 40 pin DIP became noticeably warmer, but below 30°C at 22°C room temperature.

Graham Stabler
08-31-2007, 04:25 PM
Paul, although the chip may not need additional cooling, gluing something to the top of it will actually create insulation so perhaps that could be an issue?? I'm suspecting not but who knows.

Of course if you use a thermal glue or sticky pad the socket may become a heat sink.


Fred Hawkins
08-31-2007, 05:05 PM
The one that fits best is the smallest one, which makes the uSD into a microSD. It looks to be nearly all plastic about one mm thick. The uSD is removable only if the traces of the adaptor are down, so that seems to limit it to draping it off one end or the other.