[Agile Electronics Story] The Second MLCC? ... Power Inductor for Current Control in Electronic Devices

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“Developed by applying material technology accumulated from manufacturing multilayer ceramic capacitors (MLCC) and semiconductor substrate manufacturing processes,” “Expected to grow as the second MLCC.”

Samsung Electro-Mechanics recently announced the development of the world's smallest power inductor and described it this way. A power inductor is a component necessary to supply power from the battery to semiconductors stably. So, what principle does an inductor operate on, and what kind of component is it? This edition of ‘Agile Electronics Stories’ will take a closer look at power inductors.

◆Power Inductor Controls Current with Magnetic Field... Samsung Electro-Mechanics Develops World's Smallest Product

Before understanding power inductors, let's learn what an inductor is and how it is used. When a magnetic material such as copper wire passes through a magnetic field like a magnet, or when a magnetic field passes through a magnetic material, the magnetic field changes. At this time, a force (voltage) arises that moves electricity from the higher potential side to the lower potential side. An inductor is a component that controls and releases the current flowing in a circuit through this principle. Depending on its role and structure, it is divided into communication inductors, power inductors, etc., and is used not only in electronic products but also in transformers and gasoline engine ignition plugs.

Regarding power supply, inductors and capacitors applied in MLCC have opposite characteristics. Generally, capacitors directly store and release voltage using a dielectric that induces electrical induction and electrodes through which electricity flows. In contrast, inductors are responsible for storing and releasing current through magnetic fields. Inductors and capacitors also differ in the signals and frequencies they can pass.

To operate integrated circuits (ICs) that combine semiconductors and other components, power must be supplied from a battery. Since the voltage used in ICs differs from the battery voltage, power inductors that control current flow to provide stable power supply are necessary. Power inductors are classified into wound type and thin-film type according to the coil manufacturing method. The wound type coils copper or other conductors directly around a magnetic material, which is advantageous for high capacity and current but has disadvantages in miniaturization and productivity. In contrast, the thin-film type forms a thin coil on a substrate by plating, which has the advantage of being relatively miniaturized.

The power inductor developed by Samsung Electro-Mechanics this time is of size 0804 (width 0.8 mm, length 0.4 mm), significantly reducing the area compared to the previously smallest mobile product size 1210 (width 1.2 mm, length 1.0 mm), and is an ultra-thin product with a thickness of only 0.65 mm. To develop the smallest power inductor, Samsung Electro-Mechanics independently developed raw materials applying nano-scale ultrafine powder and implemented coils with fine spacing by applying photolithography (a manufacturing method that engraves circuits using light) used in semiconductor manufacturing. A Samsung Electro-Mechanics official explained, "By utilizing MLCC material technology and semiconductor substrate technology, we were able to improve productivity and achieve miniaturization simultaneously."

◆Increasing Demand for High-Performance Electronics and Electric Vehicles... Growing Need for Power Inductors

Power inductors are essential components because they control the current in electronic devices. Although the quantity installed is still relatively less than MLCCs, so the market size is not large yet.

As the performance of electronic devices such as smartphones and tablet PCs improves, the consumption current has increased, and battery capacity to maintain usage time is also growing. Therefore, not only battery technology development but also more power inductors are needed, and they are becoming smaller.

Additionally, due to global eco-friendly policies, the production volume of electric vehicles has increased the demand for power inductors even more. The industry expects the demand for power inductors to grow by more than 20% annually in the future.

According to the global market research firm Markets and Markets, the global inductor market size is expected to grow at an average annual rate of 4.3%, reaching $3.8 billion (4.465 trillion KRW) this year and $4.7 billion (5.523 trillion KRW) by 2025. In particular, based on this, the global (chip) power inductor market size is $266.7 million (313 billion KRW) this year but is expected to grow at an average annual rate of over 4%.