[Amps] 'heat spreader' sizing ??

[Dr. David Kirkby]

On 02/ 1/11 02:42 AM, Dan Sawyer wrote:
> The project is to mount a 1KW, 2 transistor, board on a heat sink. The
> transistor centers are about 2 inches. The question is: What should the
> dimensions of the heat spreader be? I have seen dimensions of 1/4 x 2 x
> 4 up to 1/2 x 4 x 7; that represents quite a range. The questions are:
>
> 1. What thickness is required. Is 1/4 sufficient?
>
> 2. What is the minimum effective distance from the edge of the devices?
> 1/2 inch? 1 inch?
>
> Thanks,
>
> Dan

As I remarked before, I think the way to do this is to use finite element 
software. I found this, which is free for a limit of 1300 nodes, but is modestly 
priced ($50) to unlock the software, removing the limit of 1300 nodes

http://www.lisa-fet.com/

Dave

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