Single-chip digital radio receivers for consumer electronics

April 23, 2013 // By Graham Prophet
Silicon Labs' Si468x FM use software-defined radio techniques for both DAB/DAB+ and HD Radio for portable and home audio products.

Claimed to be the first single-die antenna-input-to-audio-output digital radio receiver solution developed for the global portable and consumer electronics markets and using software-defined radio technology, the monolithic Si468x receiver ICs bring FM, HD Radio and DAB/DAB+ broadcast capabilities to a wide range of audio applications, from price-sensitive clock and tabletop radios to mainstream mini/micro audio systems and CD boomboxes to high-end multimedia devices with displays such as mobile phones, tablets and personal navigation devices.

Silabs believes that digital radio adoption has been slow due in part to the high cost of delivering a high-performance yet power-efficient RF solution for the consumer electronics market. The Si468x family directly addresses the consumer digital radio market by providing an advanced, single-die solution that reduces system complexity, bill of materials (BOM) count and power consumption without compromising RF performance.

Using the company's low-IF digital receiver architecture, the Si468x family claims superior RF performance compared to existing consumer-grade digital radio solutions. The receivers support auto-calibrated digital tuning and FM-seek functionality based on multiple signal quality and band parameters and provide flexible audio processing features including noise blanking, configurable FM soft mute, FM de-emphasis and FM hi-cut filtering.

The Si468x family enables developers to reduce system cost, size and complexity by integrating most of the external components needed to build a digital radio receiver system including the RF tuner, baseband and stereo audio DACs. The family’s wafer-level chip-scale package (WLCSP) option supports very compact designs, enabling a complete digital radio receiver system with only 12 external components to be implemented in less than 100 square millimeters.

Receivers are engineered with small form factor designs in mind. By integrating the RF tuner and baseband functions on a single die, the Si468x family avoids radio self-interference and streamlines system design, validation and testing. Offering the smallest footprint and lowest power consumption of any digital radio solution on the market (less than 60 mW in analogue FM mode and