Cooling requirements?

[wardy]

I apologise if this seems a daft question, I have been watching the XMOS video's and looking over the kits - none of them feature cooling.

Now, if I were looking at a PIC MPU with it's relatively slow clock speeds, I could understand. Am I to understand that the XMOS CPU's require no additional cooling, even when running at full mips?

[leon_heller]

Some of them run hot, but they are well within specification.

[wardy]

Thank you Leon, that is very helpful.

I am conscious of the power requirements for a project I am considering and have a great opportunity to use passive cooling. As the XMOS processors aren't running too hot, my method of cooling will be simple, involve no power requirements and have no moving parts.

[Woody]

The G4s run quite hot, but I've not seen an application that requires cooling yet. However if you want to use them at full power in an ambient temperature right at the top of the valid range, then you'd need cooling.

The L1 and L2 devices run much cooler and also have AEC (Active Energy Conservation) which lowers dynamic power consumption during idle times.

You might want to check out these documents for more info:
XS1-L AEC: http://www.xmos.com/system/files/xs1lengconserve.pdf
XS1-L Power: http://www.xmos.com/system/files/xs1-l-power.pdf
XS1-G Power: http://www.xmos.com/system/files/xs1-l-power.pdf

[wardy]

Thank you Woody, I'll have a read.

I am currently in the process of designing a UAV, as a personal project. Heat can actually be useful as well as a problem. During cold weather, it can be used to keep the components of the UAV warm, possibly by using air pipes like Intel CPU's, In colder weather, it will keep the controls warm, in hot weather, in theory, it will assist in cooling.

[Jerry]

Here are some temperatures I've measured with a Tektronix IR thermometer with the boards running in a room with an ambient air temp of 25C:

XS1-L1 : 53C
XG1G4 : 81C