Small FM Transmitters Add Audio Playback To Portable Devices

By reducing the bill of materials and power consumption of existing solutions, the highly integrated Si471x family of FM transmitters lets designers add wireless FM audio playback capability to any portable media device. The transmitters come in a 3- by 3- by 0.55-mm 20-pin QFN package and consume one-third less power than competing solutions, resulting in a 33% increase in battery life, according to Silicon Laboratories. Combined with the fact that they require only two external components, that makes the transmitters well suited for use in cell phones, MP3/digital media players, navigation/GPS devices, and satellite radios.

In addition, programmable power scaling allows designers to comply with both FCC and pending European Union transmitted power regulations using one implementation. Their on-chip filtering, which reduces noise and harmonics, ensure that the transmitters easily co-exist with active cellular networks as well as GPS, WLAN, Bluetooth, and other wireless transmitters. The Si471x family's digital architecture improves the stability of volume output on the receiving system and, through unique audio dynamic range control, increases the audio fidelity of the transmitting system.

The Si4710 version is sampling now to lead customers, with prices starting at $3.91 in quantities of 10,000. The Si4711 version supports the Radio Data Service and Radio Broadcast Data Service, enabling the display of the artist and song title on an RDS/RBDS-enabled receiver. It will sample in January 2007, with prices starting at $4.69 in quantities of 10,000. A Si4710 evaluation board is available for $250. For more information, go to www.silabs.com.