Murata’s EMI Filter Division Takes up the Challenges of New Markets: Offering High Reliability and Compatibility with Large Currents Is a Feasible Mission. By Making Solution Proposals, Murata Is Working Closely with Customers Right from Its Product Planning Phase

Toru Inoue Executive Vice President and Director, Components Business Unit


After joining Murata Manufacturing in 1980, Inoue was assigned to the Accounting & Controller Dept. where, in addition to his accounting tasks, he developed collaboration with the industrial engineering department. Starting in 1990, he worked at plants in the UK and the USA and at the head office of Murata Electronics North America, Inc. before returning to Japan in 1998. He was then transferred from the Accounting & Controller Dept. to the Production Dept. at the Yokaichi Plant and from Ogaki Murata to the Corporate Planning Dept. and was appointed Vice President in 2009. Inoue became Director of the Components Business Unit in July 2013.

With every device increasingly digitalized, EMI (Electromagnetic Interference) is a great concern in the electronics industry.
The business of the Murata EMI Filter Division has two main pillars: noise suppression components and inductors. The latter is used to stabilize signals and power supplies.
These products are expected to generate increasing demand in keeping with the progress in communication technologies such as PCs and smartphones.
In the high growth potential markets of home electronics and automotive electronics, the above-mentioned Murata products are enjoying rapid growth in demand due to the increasing introduction of multifunctional devices enabled by communication technologies.
Here, offering components suitable for large current circuits and improving component reliability are the major challenges facing Murata.
We need to meet customer needs while taking advantage of our traditional expertise in communication and consumer product applications.
We have partnered with a successful supplier of a metal-based magnetic material that is needed to produce components for power lines. The Murata EMI Filter Division is now ready to address new markets and is paving the way toward next phase of growth.

The advent of PCs and mobile phones led to a sharp increase in demand. There have been steadily growing needs for noise suppression components and inductors. Size reduction, a specialty of ours, is one of the most important requirements.

Compactness, Large Currents, and High Q Demand for EMI Filter Division Products Grows with Digitalization

EMI suppression technology has recently been a focus of attention in keeping with the increasing digitalization of all equipment. Murata has been strong in providing inductors and noise suppression components that are relatively compact and used for relatively low-power lines. Looking back on our history, we supplied noise suppression components for radios and TVs as well as inductors for smoothing power supply voltage. Then the advent of PCs and mobile phones led to a sharp increase in demand. In the mobile phone market, customers primarily demand radio frequency inductors. But we also see needs for inductors for power lines. PC manufacturers have increasing needs not only for components that handle general signals. Growing wireless communications between PCs and external devices now also give rise to demand for products for radio frequency circuits. In these fields where products are increasingly commoditized, there have been steadily growing needs for noise suppression components and inductors. Size reduction, a specialty of ours, is one of the most important requirements.

One of Murata’s advantages is that we have three types of components produced using different processes: winding, thin film, and monolithic. This diversity allows us to make flexible proposals for customers depending on their needs. For example, customers who emphasize cost benefit can choose monolithic products, while performance-oriented manufacturers can be accommodated with winding technology.

With Reliable Components and Products for Large Current Circuits, Murata Is Reentering the Market for Power Products

The future of the Murata EMI Filter Division depends on how successfully we will be able to develop the market segments for home electronics and automotive electronics. The key words here are “large current and high reliability.” In the present market, non-power components represent 60% of overall demand and components for large-current power lines 40%. In four to five years’ time, however, we expect the latter’s share will increase to around 50%.

The fact is that we worked on components for large-current power lines in the past. But in the late 1980s, we were faced with increasing competition, and since then we have concentrated our resources on other fields. In the meantime, Murata has taken advantage of its outstanding downsizing technology to increase its market share with an emphasis on commodity products. So the company is now making a new attempt to enter the market for components for large-current power lines.

Product Size

Component downsizing is one of Murata’s traditional strengths. Murata noise suppression components and inductors are produced using three kinds of processes — winding, film, and monolithic — each having distinctive features. The winding process, which produces wire wound products, achieves the highest Q (quality factor) levels, but it offers only a limited scope for downsizing. Current wire wound products have become much smaller, yet they are still a few sizes larger than components produced using the film and monolithic technology. But again, their size has been reduced to 0302 (0.8 x 0.6mm). Our equipment for producing wire wound type coils also has an advantage: It is developed through a joint research program that combines Murata’s production technology with expertise of a machinery manufacturer.

On the other hand, the size of film and monolithic type products has been reduced to 01005 (0.4 x 0.2mm). Film type products have relatively high Q values, but fall short of the wire wound type. If the film process is further developed in the future to achieve Q values comparable with those delivered by the winding process, there could be a major shift in inductor size.

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