Silicon Labs Expands FM Receiver Portfolio

The new Si4704 and Si4705 incorporate all of the world-class features found in Silicon Laboratories CMOS Si4700 FM tuner family and are the industry’s first to support an embedded antenna. The patent-pending tunable resonance circuit incorporated on-chip provides optimal signal reception and excellent sound quality with a short embedded antenna, such as a wire or PCB trace that can be integrated inside the end product casing, enabling FM radio to be added to any portable device without the need for an external headphone cable. This enables a truly wireless music experience for FM recording, clock radios and FM over speaker applications where a headset is not required. It also complements products with integrated Bluetooth® technology by allowing consumers to listen to radio over wireless headsets without having to attach a headphone cable to their portable receiver.

In addition, the Si4705 provides a digital audio interface that allows easy recording of FM radio without the need for external analog-to-digital converters, saving power, cost and board space. Requiring only 15 mm2 of board space, Si4704/05 are layout-compatible with Silicon Labs’ Si4710/11/12/13 FM transmitter, Si4720/21 FM transceiver and Si4730/31 AM/FM receiver, enabling one common platform among multiple designs. Both devices provide coverage of the expanded worldwide FM frequency band from 64 to 108 MHz.

The new third-generation Si4708 and Si4709 FM receivers are the industry’s smallest and highest performance FM receivers, reducing required system board space by 44 percent compared to competing solutions to simplify design, save cost and improve manufacturability. These new devices require only 8 mm2 of board space and are packaged in a 2.5- x 2.5-mm QFN package that is easy to assemble and forms robust solder joints without requiring any under fill or mechanical reinforcement. In addition to the small size, the Si4708 and Si4709 offer advanced FM seek algorithms, allowing consumers to more quickly seek and lock to available FM stations. The devices provide excellent selectivity using Silicon Labs’ proven digital low-IF receiver architecture, allowing consumers to listen to more channels with less interference than competing solutions. The Si4709 is the smallest FM receiver in the industry to provide RDS functionality.

“Silicon Labs is the leader in single-chip AM and FM solutions and has shipped more than 100 million units of its proven, patented technology to customers worldwide,” said Mark Thompson, general manager of broadcast audio products. “Reducing board space and continually improving the end-user experience are paramount concerns for our customers who rely on Silicon Labs’ products to help them achieve these goals. With the addition of these four new devices, we further increase our value proposition in terms of size, performance, innovative new features and price.”

A full reference board with complete schematics, layout files and a robust software development environment is available to customers to facilitate evaluation and design and dramatically reduce development time compared to competing solutions that require a maze of components, which drives many manufacturers to buy expensive FM modules. Samples of the Si4704, Si4705, Si4708 and Si4709 are available now.