The regulating tube of switching power supply works in saturation and cut-off state, so it has small calorific value, high efficiency (more than 75%) and saves a large volume of transformer. However, a large ripple (50mvat5voutputtypical) will be superimposed on the DC output of the switching power supply, which can be improved by connecting the zener diode at the output end in parallel. In addition, because the operation of the switching tube will produce great peak pulse interference, it is also necessary to connect magnetic beads in series in the circuit to improve it. Relatively speaking, the linear power supply has no above defects, and its ripple can be made very small (below 5mv). For the switching power supply, the main wiring terminals are fence terminals, such as 9500825611 and other terminals.
Switching power supply is preferred where power efficiency and installation volume are required, and linear power supply is preferred where electromagnetic interference and power purity are required (such as capacitance leakage detection). In addition, when isolation is needed in the circuit, DC DC is now mostly used to supply power to the isolated part (DC DC is a switching power supply from its working principle). In addition, the high-frequency transformer used in switching power supply may be troublesome to wind.
For the linear power supply, the regulator's regulating tube works in the amplification state, so the calorific value is large and the efficiency is low (about 35%), so it is necessary to add a large heat sink, and it also needs a large power frequency transformer. When multiple groups of voltage output are to be made, the transformer will be larger. In terms of the use of wiring terminals, the connectors mainly used by the linear power supply, such as xh2 54 terminals, etc
