I have cooked 3 regulators applying 12 V to RAW pin. Am I doing something wrong or did I get a bad batch? I'm trying to make a simple keypad lock that has a 12 V magnetic lock.  I supplied 12 V to the RAW pin on the Pro Mini with plans to actuate the relay with the 5 V from VCC pin.  The lock was grounded on the terminal strip that the 12 V came from, and then the positive 12 V was switched through the relay.

Everything was working well until I powered the board through the RAW pin with 12 V.  When I did that all three failed the smoke test.

My question is, am I doing something incorrectly or did I happen to get a bad batch (all three of the boards came in the same shipment, I assume they came from the same lot)?
The Pro Mini's 5V regulator (MIC5205) can supply a maximum of 150 mA, from which the Pro Mini uses about 20 mA, leaving around 130 mA for other applications.



Check the data sheet of the relay, to get the maximum current draw. For example, the RWH-SH-105D relay requires around 70 mA in the "on" position. While this is under the 130mA limit, you may be using other IOs or powering other modules.

To reduce the current draw, use a transistor to drive the relay like this: