Will it be safe to run a pro mini on 12v regulated into raw input, with 30mA of current for 24/7, without the risk of damaging it in the long run? The setup will be enclosed in a non airtight ABS project box with a wireless transceiver. The regular on the pro mini seems warm, not hot, to touch after a few minutes. Or is it advisable to run it through a LM7805 first?
The total heat in that box will be generated by the 12V with 30mA = 0.36 Watt.
The heat by the voltage regualator is 12V - 5V with 30mA = 0.21 Watt.
You can use an extra power regulator, or diodes or a resistor. The total will still be 0.36 Watt.
Can the heat go through the walls of the box to the outside ? Or is it encapsulated in foam or is the sun shining on it ?
Since it is receiving, I assume that you can not put the Pro Mini into sleep mode ?
To make it cooler, you can use a DC-DC converter, however I think that is not needed, since it is only 0.36 Watt. Unless it is a very small box, and it has not enough cooling through the walls.
To make the voltage regulator on the Pro Mini board less hot, you could use a voltage regulator, but also a few diodes or even a resistor. I hope you know that a LM78xx needs capacitor, or else it might start oscillating.
Thanks Peter, everything I needed to proceed was in your reply. Appreciate it.