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STMicroelectronics Boosts Music-Phone User Experience
STMicroelectronics has introduced an IC that delivers superior sound quality from portable music players and feature-phones by excluding high-frequency interference from cellphones. This new device is ideal for the growing number of cellphones being shipped with music-playback capabilities, which iSuppli predicts will grow to exceed one billion handsets annually by 2010, representing more than 90 percent of the market. It will also protect other portable music devices against interference from nearby cellphones.
The Although a small number of single-chip alternatives are available, only ST’s filtering and protection IC provides circuits that are individually optimized for the earphone and microphone connections, which require different filter characteristics. ST has achieved this by combining its existing EMIF02-MIC03M6 and EMIF02-SPK02F2 for microphone and speaker interfaces into a single integrated device. Features to help maximize handset battery life include low-resistance earphone circuitry (0.3 Ohms), resulting in efficient driving of the speakers.
In addition to its highly integrated and optimized filtering, the new IC also provides required protection against electrostatic discharge (ESD) capable of damaging the handset’s internal components. By protecting against ESD spikes up to 30kV in direct contact with the signal connections, this new device is more effective than passive ESD-protection components.
The EMIF04-EAR02M8 is available in a micro-QFN 8-lead package, priced at $0.24 for orders over 10,000 units.