This heatsink temperature monitor circuit signals via 3 LEDs when the temperature exceeds 2 boundary levels. When the heatsink temperature is below 50 … 60 o C (122 … 140 o F) the greed LED lights.

This circuit can be used to determine the core temperature of your PC’s CPU and display it on a monitor (Fig. 1). Installing such a circuit can help to ensure that your system’s cooling is ...