What should be paid attention to in the application of power module?

1. Extremely light load use

Generally, the minimum load limit of the module power supply varies from manufacturer to manufacturer, usually about 10%. Because the load is too light, the current carrying element is difficult to continue to flow, and the current is discontinuous, resulting in unstable output voltage. This is caused by the power supply itself.

What if the user does use it with light load or even no load? The most convenient and effective method is to add a certain false load, which is about 2% of the output power. It can be preset by the module manufacturer before leaving the factory, or the user can install appropriate resistors outside the module as loads. If the former is selected, the module efficiency will be reduced. However, some circuit topologies do not have a minimum load limit.

2. Multiple output power distribution

When selecting the power supply of multiple output modules, please pay attention to the power distribution between different outputs. Take two-way products as an example. Generally, there are two types: one is bidirectional balanced load, that is, the bidirectional current is the same; The other is unbalanced load, that is, the load current of the main and auxiliary roads is different, the main road is larger, and the auxiliary road is smaller.

For such products, it is recommended that the ratio of auxiliary road power to main road power be 1 / 5~1 / 2. Within this range, the voltage stability of the auxiliary road is guaranteed (within 5%), otherwise the auxiliary circuit voltage will be high or low. On the other hand, if the bidirectional loads are different, please try not to use the balanced load module power supply, because the power supply is designed for symmetrical loads. If the load is unbalanced, the voltage accuracy of the auxiliary circuit is not high.

3. Try to reduce the temperature rise of module power supply

The working temperature of the internal components of the module directly affects the service life of the module power supply. The lower the device temperature, the longer the module life. Under some working conditions, the loss of the module power supply is certain, but by improving the heat dissipation conditions of the module power supply, the temperature rise of the module power supply can be increased, thus greatly extending the service life.