A temperature activated switching circuit 100, comprising a temperature activated switch U1 for switching an output 102 at a threshold temperature, the temperature activated switch U1 having at least one power input VCC for receiving power; and power switching circuitry for connecting a power source to said power input VCC of the temperature activated switch U1, the power source being initially disconnected from the power input VCC, and the power switching circuitry being configured to connect said power source to the power input VCC based on a detected temperature, in order to power up the temperature activated switch U1 before said detected temperature reaches said threshold temperature.