How to choose the switching power supply?

As the heart of the electronic equipment, the switching power supply plays an important role in the safe and reliable operation of the electronic equipment.

Switching power supplies a part of power at work and is released in the form of heat.

The problems that need to be considered when choosing the switching power supply are:

1, in order to improve the reliability of the system, it is recommended that the switching power supply work at 50%-80% load. That is to say, if the power is 20W, the switching power supply with output power of 25W-40W should be selected.

2. Try to choose the standard power supply of the manufacturer, including the standard size and the output voltage. In this way, the delivery will be faster; on the contrary, the special size and output voltage will increase the development time and cost.

3, define the range of input voltage. Taking AC input as an example, the commonly used input voltage specifications are 110V and 220V, so there are three kinds of specifications of 110V, 220V AC switching and universal input voltage (AC:85V-264V). The input voltage specification should be selected according to the area of use.

4, switching power supply will consume part of the power and release it in the form of heat, so users should consider the heat dissipation of switching power supply in the system design (especially closed system).

5, according to the service condition, set the output voltage and current needs; power supply size, installation method and installation hole; there are several outputs, each output is electrical isolation; input voltage range; according to the ambient temperature, determines the derating degree, the switching power supply power supply power; the need for authentication and safety standards cooling mode: power supply; natural cooling or forced air cooling; EMC standard.