news

In response to the global trend of intelligent energy conservation, wireless communication and portable mobile device products are required to be designed with high efficiency and low power consumption. Therefore, the power inductor responsible for energy storage conversion and rectification filtering within the power module plays an important energy-saving component role.

At present, the performance of ferrite magnet materials is gradually unable to meet the miniaturization and high current requirements of power inductor products. It is necessary to switch to metal magnetic cores with high saturation magnetic beams in order to break through the technical bottleneck of the next generation of micro/high current products and develop high-frequency, miniaturized, high packaging density, and high-efficiency power modules.

At present, the technology of integrated metal inductors is becoming increasingly mature, and another development direction is high-temperature co fired layer chip based metal power inductors. Compared to integrated inductors, these types of inductors have the advantages of easy miniaturization, excellent saturation current properties, and low process cost. They have begun to receive attention from the industry and have been invested in research and development. It is believed that in the near future, metal power inductors will be widely used in various mobile products, To meet the trend of intelligent and energy-saving applications.

Principles of Power Inductor Technology

The operating principle of the power inductor used in the power module mainly stores electricity in the form of magnetic energy in the magnetic core material. There are many forms of application for inductors , and the types of magnetic core materials and component structures used in each scenario have corresponding designs. Generally speaking, the ferrite magnet has a high quality factor Q, but the saturated magnetic beam is only 3000~5000 gauss; The saturated magnetic beam of magnetic metals can reach over 12000~15000 Gauss, which is much more than twice that of ferrite magnets. According to the theory of magnetic saturation current, compared to ferrite magnets, magnetic core metals will be more conducive to product miniaturization and high current design.

When the current passes through the power module, the rapid switching of transistors results in transient or sudden peak load current waveform changes in the power inductor, making the characteristics of the inductor more complex and difficult to regulate.

The inductor is composed of magnetic core materials and coils. The inductor will naturally resonate with the stray capacitance existing between each coil, forming a parallel resonance circuit. Therefore, it will generate a Self resonant Frequency (SRF). When the frequency is higher than this, the inductor will exhibit capacitance, so it can no longer have energy storage function. Therefore, the operating frequency of the power inductor must be lower than the self resonant frequency to achieve energy storage effect.

In the future, mobile communication will develop towards 4G/5G high-speed data transmission. The usage of inductors in high-end smart phones and the market have begun to show strong growth. On average, each smart phone requires 60-90 inductors. In addition to other modules such as LTE or graphics chips, the usage of inductors in the entire phone is even more significant.

At present, the unit price and profit of inductors are relatively high compared to capacitors or resistors, attracting many manufacturers to invest in research and production. Figure 3 shows the IEK’s evaluation report on the global inductor output value and market, indicating strong market growth. Figure 4 shows the analysis of the scale of inductor usage for various mobile devices such as smartphones, LCDs, or NB. Due to the huge business opportunities in the inductor market, global inductor manufacturers are actively exploring handheld device customers and making every effort to invest in the research and development of new power inductor products to develop efficient and low-power intelligent mobile devices.

The derivative applications of power inductors are mainly in automotive, industrial, and consumer electronic products. The types and specifications of power inductors corresponding to each application situation are different. Currently, the largest application market is mainly consumer products.