IC shields against high frequency interference

The EMIF04-EAR02M8 device from semiconductor supplier STMicroelectronics, measures 1.5 x 1.7mm and has been designed to replace the network of components or separate ics traditionally installed in music players' headset connection circuitry. According to ST, this can save as much as 72% of pc board space and leave room for the implementation of further features. An attenuation of signals at frequencies from 900 to 1900MHz allows its use in handsets for all cellular standards, as well as multiband products. While other single chip alternatives are available, ST says that by combining two of its existing interfaces into a single integrated device, its filtering and protection ic is the first to provide circuits that are individually optimised for the earphone and microphone connections. Features designed to help maximise handset battery life include low resistance earphone circuitry (o.3Ohms), while the ic is also said to provide protection against electrostatic discharge.