The Silicon Labs Si476x auto radio tuner family consists of 10 devices with different band coverage and features. All of the tuners provide performance gains over existing devices.

We take car radios for granted these days. But over the years, they have grown much more sophisticated with lots of new options. Besides the classic AM/FM coverage, you now can get satellite radio coverage and HD Radio. Radio data system (RDS) additions to the FM radio also have become more common for information and navigation. Automotive radio design certainly is more challenging than ever.

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The Silicon Laboratories Si476x family, though, aims to give designers more options. These tuners provide a best-in-class multiband receiver solution for automotive infotainment head units and AM/FM car radios of all classes. This year, global automotive sales are expected to exceed 76 million units, each with a radio—and that doesn’t include the radios on the aftermarket (see “Mobile Technology Drives Premium Automotive Audio Markets Too”). And these markets always are looking for a better radio.

The Si476x leverages the company’s patented digital low-IF technology and combines most of the traditional external bill of materials into a highly integrated, single-chip CMOS solution. It supports all worldwide broadcast radio bands including AM/FM, college FM, longwave (LW), shortwave (SW), NOAA weather band, FM RDS decoding, and AM/FM HD Radio reception. IBiquity Digital Corp., which developed HD Radio, has certified the Si476x family to provide AM/FM HD Radio tuner outputs and reception with compatible HD Radio demodulator ICs.

HD Radio provides a coded orthogonal frequency-division multiplexing (OFDM) overlay of compressed audio on the same frequencies used in the AM and FM bands. Radio stations adopting HD usually transmit the same content on the digital signal. However, the digital format also provides a way for stations to introduce one or two new subchannels of alternate programming. Already, approximately 2000 stations in the U.S. are transmitting HD. The benefits, of course, are less susceptibility to noise and fading as well as improved audio frequency response nearly equaling CD quality on FM and near FM quality on AM.

One key advantage of the Si476x family provides an alternative to enable developers to pair a best-in-class tuner IC with the optimal choice of audio digital signal processors (DSPs) to create the most cost-effective back-end audio processing designs. Silicon Labs has partnered with Cirrus Logic and Freescale Semiconductor to deliver comprehensive audio system solutions that break the expensive partitioning approach required by some car audio solutions.

The superior linearity of the Si476x tuner’s integrated RF front end, combined with a high-performance on-chip radio DSP and microcontroller, delivers outstanding RF dynamic range and immunity to multi-path fading. With this architecture, the Si476x family raises the bar for such key features as selectivity, sensitivity, third-order intermodulation distortion (IMD3) break-in, desensitization, noise blanking, weak signal processing, dynamic channel bandwidth control, and advanced dual-tuner FM phase diversity reception.

Samples and production quantities of the Si476x are available now in a compact 6- by 6-mm, 40-pin quad flat no-lead (QFN) package. Pricing begins at $11.62 in 10,000-unit quantities. The Si4763LNA-A-EVB and Si4767PD-A-EVB evaluation boards are available to automotive customers for $450.

Silicon Laboratories Inc.        
www.silabs.com/pr/automotive-tuner.