This circular TEC (Thermoelectric Cooler) module,ATEC1−49, contains 49 pairs of Peltier elements with amaximum voltage of 5.5 Volt. Its circular shape is designedfor mounting the type of target objects which has electricalconnection leads located on the center of the bottom surface,such as laser diodes, photo detectors, CCD camera sensors,etc. This TEC module can be controlled by our TECcontroller, TECA1−5V−5V−D, to achieve high temperaturestability, < ±0.01°C, and with high efficiency, > 90%. TheATEC1−49 TEC module can be used with our thermistorsas well to achieve precise and stable temperature sensing.Figure 1.1 and 1.2 show the actual sealed version of theATEC1−49 TEC.