Hot STK500!

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#1
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The power supply part of my STK500 is usually getting frighteningly hot.
Am I the only one who see this, or is this common whit the STK500??

Does the XTAL frequency play any big part in this??

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What input voltage do you have and how much current does it draw? It is only linear regulation so a high input voltage and some current will lead to a lot of heat.

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No uC -> 100mA
   uC -> 200mA

Feeding it whit 12V from my PC PSU
so... P=U * I -> P=(12 - 5) * 0.2
P=1.4W

Didn't think 1.4 watts would be that hot... But crammed into a tight enough area, maybe it would....

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XTAL frequency has no role in the power supply temperature.

If your Vcc is seto to 5V, it will create 5 times more heat with a 15V input than with a 7V input.

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1.4 watts can be plenty in a small package, but these integrated regulators tend to be protected from overheating so I don't think it is a big problem. If you can touch it it is probably OK!