When the temperature in a room rises to a certain level, it may become an uncomfortable place to be. Well, a fan can help, but we do not want the fan on at all times, but only when the temperature rises above a particular threshold. Well, by using the TS12011 that combines an op amp, comparator, and a 0.58V voltage reference, we can build a simple temperature controlled fan circuit. Watch and enjoy and if it gets too hot, let the TS12011 take care of you.