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Tyson Clugg wrote:
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<pre wrap="">There is a switchmode power supply installed on the roof not detailed in
the images for 12V and 5V in the case we want it add ip camera at some
stage.
<a class="moz-txt-link-freetext" href="http://www.air-stream.org.au/LM2576">http://www.air-stream.org.au/LM2576</a>
And all done on one cat5e cable run :-)
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With 12V input, the LM2576 runs at around 75% efficiency giving about
3.5W of unwanted heat in a weatherproof enclosure. Is there a more
efficient IC for the job?
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There are many SMR IC's out there best would be ~90%, but generally
more expensive, or require more external components or are less
available. <br>
<br>
Nevertheless, I have yet to put a heat sink on these guys as they only
run warm to touch powering more routers requiring 2Amps. <br>
<br>
But adding a small TO220 12`C/W would more than cope if you ran them at
full rating, quite safe too as they have thremal overload and short
circuit protection.<br>
<br>
We have three of these on our network powering R100 routers one of
these has a SR2 400mW card installed and have been running for a year
now without a hitch.<br>
<br>
But I guest the main point is PoE is very easy to deploy even if your
stuck with a 5V router<br>
<br>
Robert<br>
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