Magnetic Sheets Prevent Noise from Spreading

Electrical or magnetic noise is a byproduct of electrical activity within an operating device, and it causes several types of nuisance. A device generating a strong electrical or magnetic interference (EMI) can influence a nearby device, making it malfunction or even prevent it from operating at all. The extent to which a device affects another with its electrical or magnetic fields is called its Electromagnetic Compatibility, while the extent to which a device is susceptible to external electrical or magnetic fields is called its Electromagnetic Susceptibility.

Engineers make efficient use of such electromagnetic characteristics of devices. For instance, smartphones and other devices have wireless charging technology and near-field communication. Both make use of electromagnetic fields, the first to charge the device, and the other, allowing communication with nearby devices, both without any physical connection.

The above requires effective shielding and suppression of noise from electronic products. Magnetic sheets offer one such method, with the TDK Corporation offering the latest types of noise suppressing sheets, the IFM10M, a new addition to its Flexield series. TDK claims its new magnetic sheet suppresses noise over a frequency range of 500 KHz to 10 GHz. This is useful for several types of electronic devices, such as industrial terminals, point-of-sale systems, stylus pens, notebooks, tablets, and smartphones.

Featuring a laminated design, the IFM10M series of magnetic sheets consist of a copper-plated layer and a magnetic layer sandwiched together. Although there are several other types of magnetic sheets available in the market, the IFM10M sheets are exceptional as they are only 0.04 mm thick, making them over 60% thinner than their existing counterparts, but offering the same performance. IFM10M sheets are available in sizes of 300×200 mm, with an operating temperature range of -40 to +85°C.

As the IFM10M sheets are so thin, they are well suited for slim products such as stylus pens, notebooks, tablets, and smartphones. Their thin and flexible nature allows installation in dense environments. As the design of electronic devices is making them ever thinner, electronic components are also being mounted in higher densities. The increasing density of packing electronic components together leads to increase in noise emissions from components and cables causing more interference within the device.

By using IFM10M magnetic sheets on power coils, SOCs, and attaching them to the surface of flexible boards and cables, it is possible to reduce the effects of noise emission from one printed board to another.

The new magnetic sheets can improve both electromagnetic compatibility and electromagnetic susceptibility. The noise-absorbing properties of IFM10M reduce the effect of radiated noise as applicable to radiating sources. At the same time, the sheets can also protect components and circuits that are vulnerable to emissions of external noise and thereby reduce their potential impact.

Users can cut the IFM10M magnetic sheets to desired size to fit within available space. They can even shape them as required and install them in very small gaps, as the sheets are very thin and flexible. According to TDK Corporation, the magnetic sheets can improve the sensitivity of receivers for devices using stylus as inputs as these utilize inductive coupling.