TEC (Thermo-Electric Cooler) is a semiconductor device which can cool down or heat up the temperature of an object by injecting an electrical current in one or the other direction. This TEC controller, TEC12V9A, is designed to drive a TEC at high efficiency for regulating the object temperature precisely by controlling the direction and magnitude of the current going through the TEC. It is powered by a DC voltage between 5.5V to 12V and the output current can go up to 9A without using a heat sink.