Modular power supply use four major attention

Introduction

Modular power supply in the circuit has a more extensive role, it can provide power for DSP, FPGA, microprocessors and other digital or analog loads, and to a greater extent to save space on the circuit board. For this more widely used power supply, this article will explain the module power supply in the daily use of the application of precautions.

Very light load use

General modular power supply has a minimum load limit, the manufacturers vary, generally about 10%, because the load is too light when the energy storage components to renew the current difficulties will occur discontinuous current, resulting in unstable output voltage, which is determined by the operating principle of the power supply itself. But if the user does have a light load or even no-load use of the situation how to do it, the most convenient and effective way is to add a certain amount of false load, about 2% of the output power or so, can be preset by the module manufacturer before shipment, but also by the user in the module outside the installation of the appropriate resistance as a load. It is worth noting that if you choose the former, the module efficiency will be reduced. However, some circuit topologies have no minimum load limitation, such as the E-series module power supply of DinliSign can satisfy the user's normal use from no load to full load.

Multi-output power distribution

When choosing multi-output modular power supply, pay attention to the power distribution between different outputs. Dual products, for example, there are generally two types: one is a dual balanced load, that is, the same size of the dual current; the other is an unbalanced load, that is, the main and auxiliary road load current is not the same, the main road is large, the auxiliary road is small. For this product, it is recommended to choose the auxiliary circuit and the main circuit power ratio of 1/5 to 1/2 is appropriate, in this range of auxiliary voltage stability is guaranteed (can be within 5%), otherwise the auxiliary circuit voltage will be high or low. On the other hand, if the two-way load was not the same as far as possible not to use balanced load type module power supply, because this power supply is designed specifically for symmetrical loads, if the load is not balanced auxiliary circuit voltage accuracy is not high.

Try to reduce the temperature rise of the module power supply

Module internal device operating temperature of the high and low directly affects the life of the module power supply, the lower the device temperature module life longer. Under certain operating conditions, the loss of the module power supply is certain, but can be improved by improving the module power supply cooling conditions to reduce its temperature rise, thereby greatly extending its service life. For example: more than 50W of modular power supply must be installed heat sinks, heat sinks, the larger the surface area of the more conducive to heat dissipation, and the direction of installation of heat sinks should be as conducive as possible to the natural convection of the air, the power of 150W or more than the installation of heat sinks in addition to the addition of a fan can be forced to install fan air-cooling. In addition, in high ambient temperatures or poor air circulation conditions where the module must be used to reduce the amount of power consumption to reduce the temperature rise and extend the service life.

Reasonable installation to reduce mechanical stress

Module power supply lead for metal pins, module power supply and external lines, metal pins and module power supply internal circuit are connected by welding. In some special occasions mechanical vibration intensity, especially high-power module power supply on the heat sink to be installed, this situation is more serious. Although the module power supply general internal potting thermal insulation rubber can play a good buffer protection of components, but the welding point may not withstand strong vibration stress and fracture, resulting in the failure of the module power supply, it is necessary to weld on the basis of another fixed and buffer measures, such as fixtures or bolts (for screw-hole module) will be modules and chassis, large circuit boards and other relative vibration-resistant performance of good parts fixed, and in the middle of them, the padding of good vibration. For example, you can use jigs or bolts (for modules with screw holes) to fix the module with the chassis, large circuit boards and other components that have good vibration resistance, and pad some elastic materials in the middle of them to cushion the stress caused by vibration.

Summarize

Above, is in the process of using modular power supply need to pay attention to some of the nodes. Although the applicability of modular power supply is strong, but still need to be carefully selected in order to maximize the performance of the modular power supply, and fully guarantee its reliability. Want to carry out modular power supply learning friends may wish to spend a few minutes to read this article, I believe there will be unexpected gains.