30 to 50℃ temperature control circuit

 TC620 has two temperature settings. Controlled temperature sensing integrated circuit. It can set two temperature control
points, namely high temperature point and low temperature point, and has two corresponding output terminals (upper limit, lower limit) and a separate control
output terminal. The 30-50qC fan temperature control circuit is shown in Figure 1-44. Adjust the resistance values ​​of RH and RL to set the upper and lower temperature control points respectively. The relationship between
    the resistance value and the set control temperature is determined by the following     formula: ruler = 0. 5997 × (f + 273. 15) z. 1312For     example, if the upper limit temperature is set to 50ac, then     RH =0. 5997×(50 +273. 15) 2.13[2= 133.6(kfl)