Metal Powder Composite Choke Coils Indispensable in business as well as in daily living, the personal computer has now become a standard household product. For that reason alone, marketing is greatly influenced by what can be used to entice customers. Of particular popularity recently are light-weight, compact laptops with sophisticated functions and AV PCs with large-screen LCDs. Laptops perform almost all work at an ease comparable to a desktop computer, and are required to be light, thin and moreover, have a battery supply time that would not need recharging for a one- or two-day business trip. The AV PC with its enhanced performance and multiple functions is gaining great popularity. This product is equipped with a large-screen, high-resolution LCD and enables digital terrestrial TV/DVD viewing, TV recording, image editing and more. As well, built-in wireless LAN allows Internet connectivity in any room. And even though the display is large, the trend is toward housing that enables compact storage so that the AV PC does not take up household space. Increasingly, these kinds of products have the same types of boards used in laptops. The most significant issue facing these types of PCs is the power supply and related parts. A power supply is a device that supplies power from an outlet or battery and processes it into a useable form for main components such as the CPU. In all cases, a coil component called a “choke coil” (power inductor) is used. Conventionally, the voltage of electronic components that handle main functions, such as the CPU, in enhanced-performance PCs has been lowered in order to reduce power consumption. Meanwhile, more and more electric power is being consumed to realize more functions on a PC in total. In other words, while progress is being made in energy conservation on the one hand, an increased amount of energy is being used on the other. The result is that total PC power consumption itself has changed little from before. However, a significant change is in the current required. As electric power equals voltage × current, if the voltage decreases and the PC power consumption remains the same, the outcome is a constantly increasing current. And though calls to reduce the dimensions of laptops have ceased, there is no change in the direction toward even thinner and lighter laptops, and therefore a strong demand continues for the necessary technology. These kinds of demands of the times made on the choke coil are not only contradictory but actually extremely difficult to resolve. Until recently, the majority of choke coils used were coil components with copper wire wound around magnetic cores made of ferrite. When a current is applied to the copper wire, magnetic fluxes are produced in the core. The number of magnetic fluxes has an upper limit depending on the material and the core size. Therefore, original functions cannot be performed if a current that produces magnetic fluxes exceeding this limit is applied. The result is a loss in power and heat generation. As long as the conventional ferrite is used, increasing the size of the core is the only way a larger current can be applied. However, we are caught in a contradictory situation in which increasing the core size is not permitted because of demands for lighter and thinner laptops. At the same time, choke coils assembled with bulk cores made of ferrite potentially produce a structural whining sound making them inappropriate for AV PC use. To resolve these various issues, NEC TOKIN offers the Metal Powder Composite Choke Coil.