Abstract: In recent years, micro refrigeration equipment has been widely used in communication base stations, automobile refrigerators and other fields. Because the miniature refrigeration equipment has the functions of small volume, low cooling capacity (300W), and frequency conversion function, the energy consumption is low. At present, the switching power supply of micro electronic control board in the market generally adopts the integrated chip scheme. Although it has the advantages of simple circuit and high reliability, the input voltage range is narrow, the power consumption is larger, the cost is higher, and the related heat dissipation design is also needed. A switching mode power supply based on BUCK circuit is proposed in this paper, which has the advantages of wide input voltage range, high reliability, strong load capacity and low cost.

Key words: Miniature refrigeration, BUCK circuit, Switching mode power supply