When selecting a switching power supply, multiple factors should be considered. What factors need to be considered when choosing a good switching power supply?
1. Select the appropriate input voltage range. Taking AC input as an example, the commonly used input voltage specifications are 110V, 220V, so there are three 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.
2. Choose the right power. The switching power supply consumes a part of the power during operation and releases it in the form of heat. In order to increase the life of the power supply, it is recommended to choose a model with a 30% more output power rating.
3. Consider the load characteristics. In order to improve the reliability of the system, it is recommended that the switching power supply work at 50% -80% load, that is, assuming that the power used is 20W, the switching power supply with an output power of 25W-40W should be selected.
4. If the load is a motor, a light bulb or a capacitive load, the current is large at the moment of turning on, and a suitable power supply should be selected to avoid overload. If the load is a motor, the voltage reversal during shutdown should be considered.
5. In addition, it is necessary to consider the working environment temperature of the power supply and the presence or absence of additional auxiliary heat dissipation equipment. The derated output of the ambient temperature power supply is too high a. Refer to the derating curve of ambient temperature to output power.
6. Select various functions according to application requirements: Protection functions: over-voltage protection (OVP), over-temperature protection (OTP), over-load protection (OLP), etc. Application functions: signal function (normal power supply, power failure), remote control function, telemetry function, parallel function, etc. Special functions: power factor correction (PFC), uninterruptible power supply (UPS)
7. Choose the safety regulations and electromagnetic compatibility (EMC) certification that you need to meet. According to the usage, determine the required output voltage and current; the size, installation method and installation hole position of the power supply; there are several outputs, whether each output needs to be electrically isolated; input voltage range; according to the ambient temperature, determine the drop of the switching power supply Power level, power supply power; whether certification and safety standards are required; power supply cooling method: natural cooling or forced air cooling; electromagnetic compatibility standards.
8. Try to use the manufacturer's standard power supply, including standard size and output voltage. In this way, the delivery time is relatively fast; on the contrary, the special size and output voltage will extend the delivery time and increase the cost. 9. Choose a brand. Switching power supply, as the heart of electronic equipment, plays a vital role in the safe and reliable operation of electronic equipment.