Description
   The Si4720/21 integrates the complete tuner and transmit functions for FM broadcast reception and standards-compliant, unlicensed FM broadcast stereo transmission. Users must comply with local radio frequency (RF) transmission regulations.

FEATUREs
◾Full FM RX and TX in 3 x 3 QFN
◾Worldwide FM RX band support
◾Compliant with worldwide FM TX
   regulations
◾Excellent real-world performance
◾Supports integrated TX/RX
   antenna
◾Programmable transmit output
   voltage
◾Frequency synthesizer with
   integrated VCO
◾Integrated LDO regulator
◾Minimal BOM (15 mm2)
◾Digital audio output
   (Si4721 only)
◾Digital audio input
◾Adjustable seek parameters
◾Adjustable mono/stereo blend
◾Adjustable soft mute
◾Advanced modulation control
◾Audio dynamic range control
◾Audio silence detector
◾Programmable reference clock
   input
◾2-wire and 3-wire control
   interface
◾2.7 to 5.5 V supply voltage
◾3 x 3 x 0.55 mm 20-pin Pb-free
   QFN package
◾RDS/RDBS encoder/decoder
   (Si4721 only)

APPLICATIONs
◾Cellular handsets/hands-free
◾MP3 players
◾Portable media players
◾Wireless speakers/microphone
◾Satellite digital audio radios
◾Personal computers/notebooks